The 21st November ( in Julian calendar, that some Orthodox Christian Churches still use, the date is marked as 8th of November ) in Orthodox Christian Church calendar is reserved for commemoration and celebrations of St Michael the Archangel and all other angels. In Catholic Christianity this day is known simply as; Michaelmas, it’s celebrated on 29th of September, and in European countries, it’s strangely tied to gooses, at least in folklore. It is a widespread Christian tradition (across the Europe at least) to catch a falling leaf, on this day, while walking outside and make a wish.
St Michael the Archangel, considered the Chief of Heavenly hosts, or the “chief commander of all the bodiless powers”  or Archistrategos (in Greek), is a well-known and popular archangel even to those that are not Christian. He is considered fiery, and terrifyingly powerful, but also extremely righteous and quick to help people in trouble, particularly life threatening situations. He is accounted for many miracles, some are documented in the Scripture.
Theologians think that the Angel appearing before Joshua ( Joshua 5:13-14 ) was Michael, and that he was also the Angel who was helping Archangel Gabriel defeat the Persians, even though that Michael is not named in these instances.
The pillar of cloud ( by day ) or of fire ( by night ) that led Israelites from Egypt, during the Exodus, was in fact Archangel Michael, he is also considered to be the Angel who protected Three Holy Youths, Ananiah, Azariah and Misael ( Dan 3:22-25 ), and the one who transported the Habbakuk from Judea to Babylon to feed the prophet Daniel, while he was in the lion’s den (Dan. 14:33-37 ) .
Michael disputed with the De*il over the body of Moses, as we can see in the scripture
“Yet Michael the archangel, in contending with the devil, when he disputed about the body of Moses, dared not bring against him a reviling accusation, but said, “The Lord rebuke you!” “( Jude 1:9 ) 
There are also many appearances, and miracles of St Michael, that took place all over the planet, and were recorded outside of scripture. Perhaps the most famous is the Miracle of Collosae (Chonae ) commemorated in September.
But on this day (November 21st ) all the Angels are commemorated and their deeds celebrated, and in Serbia and Montenegro, this is also a “feast day” ( Ser. “slava” ). And even though that the celebration of feast days in these parts of the world, was closely tied to several traditions and rituals, among other, the baking of special cake, cooking a special wheat meal, and ritual drinking or spilling of vine, during the “Synaxis of Archangel Michael and other bodiless powers” , these rituals did not take place. For the Angels neither have body (symbolized by the cake) nor the blood (symbolized by the vine).
However Angels, particularly Seven Archangels, were propitiated on these days and favors were asked from them, prominently. Seven candles were lit, each dedicated for one of the Seven Archangels, oftentimes each candle also being lit to represent particular wish.  I have provided the ritual, in details, in another article of mine, on this blog, also dealing with Michelmas.
The very Archangel Michael was often petitioned on this day, alone, particularly in rituals and spells against evil, to cure a longstanding chronic disease, or remove a longstanding persistent curses and crossings, end persecution, for justice and so on.
Christians traditionally pray for salvation of the their souls from sin, or the souls of their beloved ones who had gone astray ( for example turned to drugs or alcohol, gambling, or any kind of addiction or sinful lifestyle ) , for the Christians firmly believe that Michael will intervene and save them from sin, and guide them back to the path of righteousness. Among the Orthodox Christians he is often referred to as “Soul-saver” ( Serb. “dusovadnik” ) for this particular reason.
The folk tradition insists that Michael must be “paid” for his services, and that in fact, after saying
him one is to promise some kind of token
of gratitude, be it giving alms, lighting a candle in the Church for him, or
leaving a broom as a present to him.
According to same tradition, the promise given to the Michel must be
fulfilled, or else, the Saint will get angry and oftentimes even openly show it through miraculous acts and
appearances. According to the reports of pilgrims and local people, on the
small isle of Symi in Dodecanese ( Greece ) :
|Monastery of St. Michael the Archangel, Panormitis,|
“The Archangel Michael is famous in the Dodecanese for his righteous nature. If you have made an offering to him and did not fulfill it, he will make it clear through various miracles that he is not pleased - until you complete your promise. One famous miracle that occurs often and to this day, is the miracle of the Archangel preventing the boats from leaving the dock. This has become such a regular occurrence, that the Captains of the boat will announce over the PA to the passengers that someone on the boat has forgotten a promise to the Taxiarch. Once this promise is fulfilled, then and only then does the boat's engines work.” 
Taxiarch, is a Greek phrase for “Archangel”
Following are a few ideas for working with archangel Michael and other archangels and angels suitable for this day
Prayer in a bottle
Another Greek Orthodox Christian tradition, originating from the Dodecanese region.
Write down Your petition on a piece of paper and place it in a bottle. If You are afraid that someone could find, and read it, You can sign the petition with initials and date of birth, or add a personal concern of some kind to it. Pray to St. Michael for Your need, and promise something in return. Close the bottle tightly and place it into body of water, ideally into sea/ocean.
Fulfill your promise.
Celestial help, Angel invocation ritual
This ritual is best suited for Michelmas, though it can really be done anytime the need arises. However, this ritual should not be done for trivial things, or to fulfill our whims, instead the ritual should be done when there is objective or urgent need for help, or guidance. At least for a day before preforming the ritual fast, and abstain from intercourse. Also, if possible, take a cleansing bath prior to the ritual.
Place some metal objects (coins will do) in a larger white handkerchief, and tie the ends so that You get a nice, roomy pouch. Tie the ends with three knots. Alternatively, You can use a (previously properly cleansed) small bell.
Make some meringue cookies yourself. They should contain only sugar and egg white, though You can add cream of tartar, or salt so that they turn out nice. You will need four for the ritual.
Set four white or beeswax candles on four corners of the table, and next to each place a single meringue cake. Light the candles.
Ring the bell, or clank the coins tied in handkerchief. Some people do it on four cardinal directions, others ring three times and so on.
State your petition, invoke angels to help and aid You with it. You can use something like this to invoke the aid of angels:
Angeli vos invoco, in hoc loco, in hoc tempore. Liberate me ab omnium malorum, adjuvate me, custodte et gubernate. Angeli, vos imploro, exaudite orationem meum! In Nomine Dei Patris, Dei Filii et Dei Spiritus Sancti! Amen!
( Hope my Latin was good there ) Once again ring the bell/clang the coins. Let the candles burn themselves out.
Instead of stating the petition, some people write it down on a piece of paper and leave it on the table, under a glass of water that they place in the center. Either way, remember You are not evoking angels, most likely You won’t actually see them, but You might experience all sort of “paranormal” phenomena.
Following is a peculiar little ritual I have found in a local occult magazine and translated for posting here. What the ritual is supposed to do is to invoke the Archangel Uriel, to give answers to questions. Basically, it’s higher magick type divination. The ritual is following:
Cover the altar or table with a white cloth. Place in the center a glass of pure, clean spring water that has not been used for anything else. Left and right from the glass, place and lit a white candle ( so two candles altogether ) . Sit, and in front of the glass, place a metal coin or metal disc that has Cross engraved* upon it. Dip the three prayer fingers ( thumb, pointer and middle finger connected with tops ) into the glass with water, and then sprinkle some of it onto the disc/coin, while saying:
“Benedicto Dei Patris Omnipotens super vos, et maneat semper!”
Place the coin/disc underneath the glass, then kneeling in front of the table say the following:
“All Holy Angels, White Angel, my good angel guardian, I pray to You all to remove anything that can prevent Uriel to show me what I wish to see and find out in whole truth, as it is truth, as it is true that G’d had sent You to be my guardians. In gratitude, I will read “Our Father” !”
Read/say “Our Father” and then proceed with following text:
“Holy Uriel, I beseech You, by the Living G’d, Who IS Your Lord as He IS also mine, with virginity and purity of St John the Baptist, and with virginity and purity I give to You through the staff of Moses, to come to this glass of water and remain there until You have responded to all the questions I will ask You. Ghalat, Ghalata, Kalin, Kala. Welcome, bring the Book of Moses with You, open it, put Your hand on it and swear to me that You will enable me to see, what I wish to see, and I will read Our Father to Jesus Christ, and Hail Mary to Virgin Mary. “
When You start seeing something in the glass, say the following:
“Holy Uriel, I beseech You by the Living G’d ; to show me what I will ask form You, I will read Our father and Hail Mary. “
When You have gotten Your answer/s from the Angel, release the angel saying these words:
“Ite at pace, ad loca vostra, sit pax inter nos and vos” 
And that’s it. Does not really seem to have a lot of merit J but it’s worth of trying, I guess. If by any chance, You happen to know the source of this ritual ( I’m very curious about it ), please post in the comments bellow, or mail me.
Hope this post was interesting and that You have maybe learnt something new.
Blessings and luv
NOTES: This article was written and composed by myself , If You wish to use it elsewhere online, feel free, but add credits: Shadow of Shadows magick place, Shadowemail@example.com or a direct link to this post
*Allegedly the ritual dates back to Middleage, when a coin of 5 centimes that had Cross engraved on it was used. I don’t even know if such coin ever existed, but either way any round plate or metal disc with Cross will work. St Benedict’s Medallion for example.
CREDITS AND REFRENCES:
 Retrieved from: https://www.biblegateway.com/passage/?search=Jude+1%3A9&version=NKJV for educational purposes, without ill will
 According to “Kalendar za srecne dane” ( lit. Lucky days Calendar ) by Jasna Jojic Pavlovski, more about the book here http://jasnajojic.com/category/odlomci-iz-knjiga/kalendar-za-srecne-dane/
 Retrieved form: http://orthodoxwiki.org/Archangel_Michael_of_Panormitis , used here for illustrative and explanatory purposes Original text ( in Serbian ) found in “Bakini recepti za srecu I zdravlje” #18, 5th March 2013., more about the magazine here: http://www.lekiamajlija.com/?cat=462
IMAGE CREDITS: The first image is from : http://www.orthodoxarkansas.com/wp-content/uploads/Synaxis-Archangels-cropped-300x234.jpg used here for illustrative purposes without any ill will. The second image is from: http://www.panoramio.com/photo/53001209 and is used here for illustrative and explanatory purposes, without any ill will