A good friend of mine, Nutrition Momma, uses bumGenius one-size pocket diapers for her daughter. They look like this:
The bumGenuis diapers are well-made in general. I just would never recommend any kind of diaper with hook & loop (velcro) closures. Hook & loop becomes ratty, snags in the wash, and inevitably fails. I see that bumGenuis now makes the 4.0 diaper with snap closures--a wise move, in my opinion.
So here's how to convert a bumGenius hook & loop diaper to snaps:
1. Remove the loop tape from the front of the diaper. It's much easier to apply snaps without the thick piece of loop tape in the way.
2. Remove as much of the hook tape from the two side tabs without disturbing the stitching. I carefully cut a slit in the hook side with a seam ripper, then used small embroidery scissors to cut right next to the stitching. (If you have lots of time, you could always remove the hook & loop tab entirely and make a new tab.) Why do this? You want to get rid of as much hook tape as possible, to eliminate snagging. It's also really hard to put snaps through two layers of velcro.
3. Mark the spacing for your snaps. I put 10 snaps across the front and 2 on each tab. My snaps were just under 1" apart along the front.
4. Apply snaps with a snap press. The front 10 snaps (which use a socket fitting) can be inserted inside the diaper, so you don't have to put the snap all the way through the entire diaper. The tab snaps use a stud fitting, shown in the above picture. You'll need 14 caps, 10 sockets, and 4 studs for each diaper. I bought my polyacetal snaps and snap press from The Snap Store.