Then you need to lay out your material. Lay out: the lining material (I prefer flannel), the print, and the pul. Remember to put your lining and print right sides together. In this scenario the pul side should be face up. Then you cut out the material. I prefer a rotary cutter, but scissors would also do the job.
After you have cut out your material you add the snaps for the rise (since this is a os diaper) and the snaps for the front, or the velcro. Whichever you like. I suggest laying out the male and female parts of the snaps in a rough design of what you want so all you have to do is grab as you are using the press or pliers. Put the snaps through the pul and print, but not the liner. Start with the snaps nearest the middle for best results. This gives you a double layer through the snap, and a cover against baby once you turn it. After you put the snaps on align the layers like you did when you cut the fabric out. Don't worry about the tab snaps, those are the last thing.
When you pin the pul/print to the liner to sew the seam, only pin in the seam allowance. (Holes in pul = BAD!!) Typically the seam allowance is 0.25 inches, so if you have a quilting foot, get to know it. Stitch the border seam at the scant 0.25 seam allowance. Turn the diaper. Tack the elastic (12.5 inches when stretched of 0.25 inch width elastic for legs, 10 inches for back) to the leg part. I find the second rise snap to be a good part in the front, and the curve for the tab a good place in the back. Like so:
Topstitch the diaper and be aware of the elastic casings. To make the leg casings, ensure you have about a 0.375 inch topstitching seam. When stitching the casings, pull the elastic taunt so you get the bunching required once you are done. Now, you add the flap snaps and you have a fun diaper with whatever print you want! You get to do a bad thing before you put it on baby though, put it in the dryer on HIGH for about 5 minutes. This will help seal the pul around the seams.