My experience with butt toys: I started with a small plug and
advanced onto a larger one. I also have beads of several lengths but
enjoy the smaller length more. I have a long prostrate massager and it
feels like it fills me up. The next thing I am wanting is a vibrating
plug. I noticed today’s deal of the day is one of
these https://www.lovehoney.co.uk/product.cfm?p=35053 however every one
is different and what you try next is up to you. The fun thing is
trying something new and seeing how you enjoy it.
Certainly the best way is slow and steady and lots of lube. I found a selection of suction cup dildos years ago ranging in size from slim and long to short and fat. And slowly worked my way through them by sticking them to a chair and slowly riding them (using the back of the chair for support) whilst watching porn. I think it's important to be fully turned on and In position you can relax as you move. Also use anal lube it will last much longer and give you a more enjoyable experience.
I don't know if this post I just wrote is hepful... https://www.lovehoney.co.uk/community/forums/sex-toys/1723662-wow-that-was-intense/#p1723662