There are references to Flidais in several sources, the most accessible of which is a brief note in the Táin Bó Cúailnge: "Then came Flidais Fholtchaín, the wife of Ailill Find, who had slept with Fergus on Táin Bó Cúailnge, and it was she who every seventh night on that hosting quenched with milk the thirst of all the men of Ireland, king and queen and prince, poet and learner." She's referenced several times as the possessor of a wealth of cattle, deer, and other mighty herds, including the "royal oxen, called Fea and Men" and one cow, Maol the Hornless, that can produce enough milk for three hundred men by itself. That was impressive enough that even Bricriu composed a song of praise to Maol and her owner Flidais. Sometimes all wild creatures are called "the herds of Flidais". The Táin Bó Flidais from the Leabhar na h-Uidhri is all about the migration of Flidais and Her herds from Ailill Finn to Fergus mac Róich. In "Coir Annam", she is said to have the fairy power to milk deer as if they were cows, and to have passed that on to her son:
"Adammair Flidaise Foltcháin, that is Flidais the Queen, one of the tribe of the god-folk (the Tuatha dé Danaan), she was wife of Adammair, the son of Fer Cuirp, and from her cometh the name Buar Flidaise, the Cattle of Flidais. Nia Ségamain, that is ség (deer) are a máin (his treasure), for in his time cows and does were milked in the same way every day, so that he had great wealth in these things beyond that of all other kings. The Flidais spoken of above was the mother of Nia Ségamain, Adammair's son, for two kinds of cattle, cows and does, were milked in the days of Nia Ségamain, and by his mother was that fairy power given to him."
She also is a strong figure of female sexual sovereignty -- like Maeve and other Connaught-women, she takes the lovers she chooses (Adammair, Fergus, Ailill...), and her skill in that department is the stuff of legend. It was said of Fergus's sex drive, in Scéla Conchobair maic Nessa, "Seven women to curb him unless Flidais should come." The strongest traditions about Flidais that I've found are all from western Irish counties -- maybe Connaught has a thing for strong-minded, lusty women. [grin] According to James MacKillop, there's a strong oral tradition in County Mayo about Flidais's relationship with local king Ailill Finn. Heroic Romances of Ireland discusses her involvement with the Cattle Raid of Cooley, with different partisan biases depending on which text you read. (Ireland? Contentious? Never!) "The L.U. version makes Flidais assist in the War of Cualgne by feeding the army of Ailill each seventh day with the produce of her cows; she dies after the war as wife of Fergus; the Glenn Masain version, in the "Pursuit of the Cattle of Flidais," makes the Gamanrad clan, the hero-clan of the West of Ireland, pursue Maev and Fergus, and rescue Flidais and her cow; Flidais then returns to the west with Muiretach Menn, the son of her murdered husband, Ailill the Fair." ("Heroic Romances" again for that.) And as with many wealthy, sexually free sovereignty goddesses, well-being follows in her presence, and luck leaves with her. From "The Battle of Airtech", we hear of Fergus that "his householding in the east was not good after Flidais".
As one often finds with a goddess with such formidable sexuality, she has many children -- Arden, Bé Chuille, Dinand, and Bé Téite ("Lebor Gabála Érenn"), Nia Ségamain ("Coir Annam"), and Fand ("Metrical Dindsenchas"). (Wiki cites here.)
What I actually do: Practice and UPG:
Most of the rest of this is salted with my UPG and personal experience, and may not apply to others. The best way for me to connect with Flidais remains out in the wild. While I have made offerings to her successfully from my house altar, She really prefers for me to get my butt outside, even and sometimes especially if it's cold, rainy, snowing, etc. It puts me on equal footing with the creatures She takes care of, and She seems to appreciate that reminder to me that we're part of the natural world too. While I've seen websites that state that She also has a particular care for trees, I haven't seen that sourced, and other than Her preference for woodlands over any other form of habitat I haven't seen any indication of that. In my interactions with her, She's been much more concerned about either the overall health of an ecosystem, or the health of the animals within it. (Given that wild animals in general have been referred to as "the herds of Flidais", that makes total sense.)
Most of the sorts of things She tends to appreciate as offerings are forest-ranger style things, taking care of the wild spaces and helping to maintain ecological balance in the woodlands. Care of any injured wild animal also falls under this rubric, and that care may include hard endings such as shooting a rabid animal before it hurts anyone else. (I've never had to do that, but the point was made strongly to me in a vision of Hers.) She's fonder of litter pick-up combined with a good swift run than She is of material offerings and ritual. She's seemed impatient with too much formalism, so I tend to keep my rituals to her spontaneous, swift, or both. She likes poetry, in the evocative natural beauty way, not in the chanting an endless epic way. Running through the woods with loose and unbound hair (as a nod to Her title Foltchaín, the soft-haired) is one of the quickest ways to connect to Her for me, though that's more in the ecstatic practice ballpark than the service-oriented offerings of doing Her work.
I have marked UPG associations of Flidais with ivy (probably derivative of my work with the crann ogham), and She's shown up in vision to me with ivy in Her hair, or badged to Her clothes. As far as I know, though, that's just me. That has occasionally been problematic... I've volunteered for invasive weed pulls in parks before as an act of service to Flidais, only to find that they wanted me to rip ivy (invasive where I live) off trees. Eek. I got the idea that this would be a poor course of action -- I'm close to ivy as a crann ogham tree in itself, and due to my particular correllation of ivy with Flidais, it seemed like that would be a disrespectful way of helping Her wild places. I found other unrelated invasive weeds to pull. [grin]
More explicably, I also strongly associate Her with woodcraft, and tracking, stalking, hunting for food, or hunting to cull the herds all fall within Her area of expertise. (Hunting for trophies most explicitly is NOT, IME, and is one of the fastest ways to piss Her off.) She seems to mildly prefer archery over guns, but supports skilled use of either. This seems to correlate with legends about her skill in archery, and makes sense in a modern context. While She's not at all uncomfortable in cultured environments, She does seem to travel a lot. She's a civilized Goddess as well as a wild one, but she's not settled or predictable. She brings the heart of the wild into the halls of queens, and compassion and care back out into the forest. She is comfortable moving between worlds, like her hallmark beastie the deer. She journeys when She feels like it... in "Táin Bó Flidais", Bricriu lauded Her just as she was returning from a journey, and She sets out again with Fergus at the tale. Like most sovereignty Goddesses, she goes where she wants and shows up when she feels like it. Even more than most deities, just because you call her doesn't mean that she'll come, and there are times where she'll just show up on you when you weren't expecting it at all. If you're considering trying to establish a relationship with Her, she may scope you out for a while before she decides if you're worth getting to know. On a few occasions She's taken to someone immediately, but most of us have to work for it, proving trustworthiness by treating Her woods well and worthiness by demonstrating warrior or wildcrafting skills ourselves. Hey, it worked for Fergus. [grin]
I connect more strongly with Her, particularly with her sovereignty and huntress-caretaker aspects, in the fall. (This is both deer-hunting and deer mating season where I live, which probably also has something to do with it.) Common-sense warning: if you're going to go running around in the woods during hunting season trying to connect with a hunting Goddess, wear something bright and don't get yourself shot. That's not the connection you want. [grin] Despite Her appreciation of stealth and woodcraft, She's never objected to good sense -- She's very practical, in my experience.
I'd be really interested to hear from others who work with Her, if anyone does, and what y'all do.