Reddit mentions of Drawing Down the Spirits: The Traditions and Techniques of Spirit Possession

Many polytheists these days call this "horsing", a term taken from Afro-Caribbean cultures, since the person is compared to a horse, being ridden (possessed) by a god or spirit. This is a pretty good book on the topic.

Craft such as Santeria and Voodoo (and many others) have a strong spiritist leaning, with much of the work done involving putting people into a trance state where they can be 'ridden' by spirits and/or Gods. If that sort of thing interests you, I'd recommend reading this book to get a feel for the field.

I'll not go into full detail of my involvement with The Cult of Maria Lionza in Venezuela. I've tried writing it up and got 30 000 (poorly edited) words which is probably too much for this thread. At present what it means in practice is that I perform a ritualised form of worship a couple of times a week when I'm home, which involves getting myself in a suitable state of mind to talk with Her, then doing so. In return, she keeps me safe when travelling and gives me inspiration to write stories and poetry. Almost all of my writing is done either directly after one of my rituals or the following morning.

That is, though, very much an anglicisation of the religion as it is practiced in Venezuela. Which bothers me not a lot.

Meanwhile, and separately, I work Wicca in a coven. Easy to keep separate because one is group work and the other is solitary. I used to be HP, but have stepped down because of all the time abroad.

One strange thing that happened is the Yara (the real name of Maria Lionza) made clear to me the need to build a number of shrines on public land on the hill behind my house in Wales, in honour of the local deity of the land, who I (arbitrarily) refer to as Our Lady of Craiglais, where Craiglais is the old name of the hill. I would never have even thought of doing such a thing before her instruction, but they've been there for almost a decade now, and they empower me considerably.

Enough?

The other end of the spectrum would be to offer your body for full on possession by Her Upstairs. If that sort of thing sounds interesting to you, I'd recommend you read this book first.