In another post you mentioned suggestion and hypnosis - do you use props at all?
Props are any physical thing you have during a show, so in that sense yes I use props. I don't use many gimmicks, though.
To dive further into it - I basically have three main 'magic' performances: Mentalism, Side Show, Seance.
For mentalism I use as many genuine skills as possible, and the show I am currently working on will be 100% real - no deception. This was meant to be the show I began performing this year, but Covid borked that idea.
For side show it's about 50/50 real and gimmicked. That's a duo-act with my wife and we each do between two and four routines, depending on the show length. Whenever possible, I only do real skills, but if we need a longer show I'll mix in the gimmicked stuff as well.
And what about seances, how do these work?
This is a small question with a surprisingly complicated answer. I can write (and have written) quite a bit on the subject. Even the short answer isn't that short -
Short(ish) answer: Seance can either be a genuine attempt to communicate with the dead, in which case it is a religious/spiritual ritual and not entertainment, or it can be a form of interactive theater in which the audience participates directly with what's going in an attempt to have what feels like a genuine supernatural experience.
For a theatrical seance it can further divide between more spookshow style, and then more faithful Victorian-esque style.
Spookshow style is what you'll see most magicians doing, and calling it a seance. It's more like going to a haunted house attraction than a seance. And yes, that definitely has its place and can be a lot of fun, but it's not really a seance. It's more bizarre magic than anything in my opinion.
What I perform is closer to what an actual Victorian Seance would have been like, and uses very little gadgetry. There is a jump scare or two, though, just for funsies. It's advertised as an interactive theatrical experience.