On the 20th of Metageitnon, the Attic demos of Erchia held a small sacrifice to Hera. The epithet described in the surviving material is listed as 'Thelkhinia' (Oελχινια), but it is the only mention made of that epithet anywhere--it also doesn't mean anything in the ancient Greek tongue. Most likely is that there was a spelling error, and the 'h' needs to be removed, leaving the more commonly used epithet 'Telkhinia' (Τελχινια). If this is the case, the epithet most likely refers to a place title: 'Of Telkhinia', located in Cyprus. Pausanias describes this epithet (and a temple to this epithet) for Athena in Boiotia. The description is from his 'Description of Greece':

"In Teumessos [in Boiotia] there is also a sanctuary of Athena Telkhinia, which contains no image. As to her surname, we may hazard the conjecture that a division of the Telkhinians who once dwelt in Kypros came to Boiotia and established a sanctuary of Athena Telkhinia (of Telkhinia)." [9. 19. 1]

Diodorus Siculus, in his 'Library of History', however, gives an extended account of the cult title--in this case it does not refer solely to Telkhinia, but to four mysterious magician-smiths and/or sea daimones native to the islands of Keos and Rhodes. There are others who describe these smiths as well, and they all describe them as excellently skilled, but that is where the similarities end. To some ancient writers, they are cultivators of the soil and ministers of the God, to others, sorcerers and envious daimones, and to others again, skilled artisans. Diodoros subscribes to the latter theory, and he makes mention of Hera Telkhinia:

"The island which is called Rhodes was first inhabited by the people who were known as Telkhines (Telchines); these were children of Thalatta (the Sea), as the mythic tradition tells us, and the myth relates that they, together with Kapheira (Capheira), the daughter of Okeanos (Oceanus), nurtured Poseidon, whom Rhea had committed as a babe to their care. And we are told that they were the discoverers of certain arts and that they introduced other things which are useful for the life of mankind. They were also the first, men say, to fashion statues of the gods, and some of the ancient images of gods have been named after them; so, for example, among the Lindians there is an ‘Apollon Telkhinios’, as it is called, among the Ialysians a Hera and Nymphai (Nymphs), both called ‘Telkhinian’ and among the Kameirans a ‘Hera Telkhinia’. And men say that the Telkhines were also wizards and could summon clouds and rain and hail at their will and likewise could even bring snow; these things, the accounts tell us, they could do even as could the Magi of Persia; and they could also change their natural shapes and were jealous of teaching their arts to others. Poseidon, the myth continues, when he had grown to manhood, became enamoured of Halia (Brine), the sister of the Telkhines, and lying with her he begat six male children and one daughter, called Rhodos, after whom the island was named. [...] At a later time, the myth continues, the Telkhines, perceiving in advance the flood that was going to come [Deukalion's flood], forsook the island and were scattered. Of their number Lykos (Lycus) went to Lykia (Lycia) and dedicated there beside the Xanthos River a temple of Apollon Lykios (Lycius). And when the flood came the rest of the inhabitants perished,--and since the waters, because of the abundant rains, overflowed the island." [5. 55. 1]

All we know for sure is that at Erchia, the sacrifice was of an all-black, female, lamb that cost seven drachmas. The sacrifice was not a holókaustos, so the festival goers would have shared in the little meat the animal possessed. the cut for the Gods was not to be removed from the altar. Female victims were reserved for female Gods; all-black victims usually to khthonic deities. If that was the case, the belief could have been that thy were appeasing envious daimones rather than artisans. In this much later (5th century A.D.) account by Nonnus, in his 'Dionysiaca', the Telkhines are described as such:

"[When Rheia summoned gods to join Dionysos in his war against the Indians:] The spiteful Telkhines (Telchines) also came also to the Indian War, gathering out of the cavernous deeps of the sea. Lykos (Lycus) came, shaking with his long arm a very long spear; Skelmis (Scelmis) came, following Damnameneus, guiding the seachariot of his father Poseidon. These were wanderers who had left Tlepolemos's land [Rhodes] and taken to the sea, furious Daimones of the waters, who long ago had been cut off from their father's land [of Rhodes] by Thrinax with Makareus (Macareus) and glorious Auges sons of Helios (the Sun); driven from their nursing-mother they took up the water of Styx with their spiteful hands, and made barren the soil of fruitful Rhodes, by drenching the fields with water of Tartaros." [14. 36]

There is no mention of a daylight or nighttime sacrifice, but due to the lack of a holókaustos, I assume it would have been a daytime offering. The records make no note of a wineless sacrifice, so wine was most likely involved. There is much unknown about tomorrow's sacrifice, but perhaps this will give you an idea, regardless, to whom you are sacrificing.