I crochet things sometimes. Usually things without button holes. And then I decided I would like to button them. I've invented (?) a solution for this problem. It's a little piece of chain, maybe 2" long with a nice big lobster clasp at either end. Now you need is two buttons with a shank into which you can fasten the lobster clasp. The buttons can be as big as you like because it's only the clasp that passes through some convenience space in your crochet - then you attach the buttons. It also means the buttons are interchangeable.
I've made other fastenings in this style by attaching the shank of the button to the chain with a jump ring. This makes a kind of giant cuff link. The downside of this is you need a hole large enough for the button to pass through and the buttons are attached for keeps, not interchangeable.
A difficult thing to describe in words but a very useful invention - or unvention as Elizabeth Zimmerman would say!