Gaining

Why do you want to gain? If you have a reason to gain, the amount should be obvious to you.

I disagree.

True, someone can start easy, and see how it feels.

But I don't understand someone wanting to know how much to gain. It's like going to a bar and asking how much to drink. If you do something for pleasure, you should have some idea how much pleases you. Some feedees just want a few curves. Others want to be immobile.

Seems to me you should gain at least 10% (22 lbs in your case) of your current weight or it won't even be that noticeable. And of course if that isn't enough, you can always gain more!