I usually add batting in between - and make mine reversible. There are many cute in the hoop designs out there!! Good luck!! Hugs, Laura*

There is a fabric called "Pul" which is for baby things. Its waterproof and comes in so many cute baby designs.

I should have added to this post that I would be embroidering on them.

I use cotton fabric and put towelling in the middle and make mine reversible. I hoop the fabric and towelling and embroider the front and use a contrast for the back with no embroidery. Depending on where you are and whether you want something to dry faster you could out cotton flannel inside. Just wash everything first.
If you click on my name you will see a picture of some bibs I did a while ago.

Do you live where there are Walmarts? They have a pack of tiny baby bibs of thin terry backed by plastic/vinyl that barely fit my 4 x 4 hoop. Very servicable and no sewing, just embroider. There's usually a girls' colors pack and a boys' colors pack

I make mine in the hoop and use flannel on the back and front and batting in the middle.

Hi Kiki,
Check out the post, go through the Sewing posts for lot of place for free patterns.
You can make bibs out of almost anything. Buy premade terry, or quilted. Make your own and bind with bias strip, or sew and turn right side out for covered stitches.
Terry, pre-quilted, old T shirts ( super clean, obviously) cottons. You can use a flannel backed table cloth with the flannel side out as a backing. Limitless.
Jo