Oilcloth - I purchased 1/2 yard of Anna Maria Horner's oilcloth, which is slightly wider than standard fabric. It is 55" wide versus the standard 44". Oilcloth is a great choice for a changing pad because it's water resistant and it's slick, so it can be wiped down.
Flannel - I wanted the other side to be soft and absorbent, so I chose flannel. I pieced Anna Maria Horner's Folksy Flannel for the soft side.
1. Cut the 1/2 yard of oilcloth in half vertically, so you have two pieces that are approximately 18" x 27.5".
2. Take one piece of the oilcloth and cut it so it's square.
3. If you are using a solid piece of flannel, cut it to the size of the oilcloth. I pieced my flannel slightly larger than the oilcloth piece, planning to square it later.
4. The next step is to make a batting-flannel-oilcloth sandwich. Lay the batting down first and smooth out any wrinkles. Next, lay down your flannel right side up. Place the oilcloth on top of it right side down. Your flannel and oilcloth will be right sides together.
5. Pin all three layers together
6. Cut the flannel and batting so they are square with the oilcloth.
7. Starting toward the center of one of the short sides, sew a 1/4" seam all the way around, stopping about 6 inches away from where you started. Leave enough room to get your hand inside for when it's time to turn it right side out.
8. Trim the corners, being careful not to cut into the seam.
9. Gently turn it right side out. If you pull too hard, the batting can pull out from the seam.
10. After it's turned right side out, use your fingers or a turning tool to poke out the corners.
11. Pin the opening closed.
12. Topstitch all the way around, about 1/8" from the edge.
That's it - you now have a changing pad!