Gaining

I'd suggest until your current clothes feel tight. Buy a couple of larger pieces, and see how you like how you feel and look.

Some say 10%, others say enough that other people will notice. Which is probably close to 10%.

See fantasyfeeder.com/forum/posts

I agree that a test run is a good way to see if it's for you. I didn't give myself a test weight, but a test time; I took a week to live like a gainer (which turned into 8 or 9 days), to see how much weight I could gain and how I felt about it. I then I took a little bit of time to think about it, and I found myself just going for it until I hit a relatively happy weight/lifestyle. I will say, I did get a bit caught up in the rush of finally going for it during that test week! But as I got closer to my long-term goal, I found it much easier to feel in control of my fetish, mostly because I understood it better, and because I felt more fulfilled with a fatter body.

Finally giving in and giving it a go was one of the best decisions of my life to date. I love my body now! I highly recommend giving it a try. If it's not for you, you'll know soon enough