This is from my old blog.
This is the ritual that I’m using for the Libations to Dionysus. I get most of my information from ‘In Praise Of Olympus: Prayers to the Greek Gods’ by Hearthstone. I hope that this ritual helps out and that you enjoy it. Change if need be.
1) Purify the Altar area.
2) Take the barley and say, “As it was done in ancient times. I purify and cleanse this altar with this barley. With this barley I purify this altar and space so that I may give offerings, libations, and speak with glory and respect the gods of Mt. Olympus.”
3) Light a candle and say a hymn to Hestia.
Hestia, you who guard the sacred shrine of the Lord Apollon. The far-darter at goodly Pathos. With soft oil dripping ever from your locks. Come now to this house, come having one mind with Zeus the all wise-draw near, and with all bestow favor upon my song.”
4)Prayer to Hestia
Hestia, gracious goddess who sits at the heart of each home, who lives in the heart of each one who reveres you, each one who holds you dear, each one who turns to you for strength and harmony.
Hestia, goddess most needful, goddess most serene, goddess most esteemed, the heart of the city is yours as well, great goddess; within your realm are those who serve the state, who work for all the good of all–your blessings fall on the honest, goddess, your wrath on the corrupt, on those who betray their trust for gain. Defender of the householder, guardian of the hearthfire, Hestia, I praise and honor you.
5) Let Dionysus know that your there. Say this by saying, “Dionysus, here me.” This isn’t a command, this is letting him know that your here. Let him know any offerings that you’ve given him including incense, wine, or juice, and food. Then tell him why your here.
6) Speak the epithets of Dionysus. This is different than when you did your ritual to Zeus. I choose three (giver of unmixed wine, wild, and with balls, with testicles), in the past I’ve given you offerings (list offerings, if you have given them), incense (list incense, if you want), and libations (list libations that you’ve given) and then tell Dionysus why your here.
7) Say a hymn to Dionysus. I chose this one
 I will tell of Dionysus, the son of glorious Semele, how he appeared on a jutting headland by the shore of the fruitless sea, seeming like a stripling in the first flush of manhood: his rich, dark hair was waving about him,  and on his strong shoulders he wore a purple robe. Presently there came swiftly over the sparkling sea Tyrsenian1 pirates on a well-decked ship —a miserable doom led them on. When they saw him they made signs to one another and sprang out quickly, and seizing him straightway  put him on board their ship exultingly; for they thought him the son of heaven-nurtured kings. They sought to bind him with rude bonds, but the bonds would not hold him, and the withes fell far away from his hands and feet: and he sat with a smile  in his dark eyes. Then the helmsman understood all and cried out at once to his fellows and said:
“Madmen! what god is this whom you have taken and bind, strong that he is? Not even the well-built ship can carry him. Surely this is either Zeus or Apollo who has the silver bow,  or Poseidon, for he looks not like mortal men but like the gods who dwell on Olympus. Come, then, let us set him free upon the dark shore at once: do not lay hands on him, lest he grow angry and stir up dangerous winds and heavy squalls.”
 So said he: but the master chid him with taunting words: “Madman, mark the wind and help hoist sail on the ship: catch all the sheets. As for this fellow we men will see to him: I reckon he is bound for Egypt or for Cyprus or to the Hyperboreans or further still. But in the end  he will speak out and tell us his friends and all his wealth and his brothers, now that providence has thrown him in our way.”
When he had said this, he had mast and sail hoisted on the ship, and the wind filled the sail and the crew hauled taut the sheets on either side. But soon strange things were seen among them.  First of all sweet, fragrant wine ran streaming throughout all the black ship and a heavenly smell arose, so that all the seamen were seized with amazement when they saw it. And all at once a vine spread out both ways along the top of the sail with many clusters hanging down from it,  and a dark ivy-plant twined about the mast, blossoming with flowers, and with rich berries growing on it; and all the thole-pins were covered with garlands. When the pirates saw all this, then at last they bade the helmsman to put the ship to land. But the god changed into a dreadful lion there on the ship,  in the bows, and roared loudly: amidships also he showed his wonders and created a shaggy bear which stood up ravening, while on the forepeak was the lion glaring fiercely with scowling brows. And so the sailors fled into the stern and crowded bemused about the right-minded helmsman, until suddenly the lion sprang upon the master  and seized him; and when the sailors saw it they leapt out overboard one and all into the bright sea, escaping from a miserable fate, and were changed into dolphins. But on the helmsman Dionysus had mercy and held him back and made him altogether happy, saying to him:
 “Take courage, good…; you have found favour with my heart. I am loud-crying Dionysus whom Cadmus’ daughter Semele bare of union with Zeus.”
Hail, child of fair-faced Semele! He who forgets you can in no wise order sweet song.
(8) Pour libation to Dionysus.
(9) End with the prayer to Hestia
“Hestia, goddess of home and hearth, to you I offer last of all as a pious mortal should. Tend to those whom I love and guard the houses of the pious. As the gods will it, so it shall be.”
It is so!
Dump the entire container that you’ve poured your wine or grape juice into outside and then that ends it.