There is an infinite number of ways to make cloth bookmarks. Here is how I make mine.

1. Measure and cut a piece of fabric, 2 inches longer and twice+1 inch the width you want to end up with. Or, just cut what looks right. The piece here is 9 x 5 in.

2. Fold (wrong sides facing) 1/8th of an inch in one of the narrow sides and press.

3. Fold (right sides facing) the whole piece in half lengthwise and press.

4. Cut a piece of ribbon a bit longer than your fabric.

5. Open up the folded fabric, pin and sew the ribbon on one of the two right sides of the fabric. Use a color that matches the ribbon, and sew very close to the edges.

6. Fold the fabric again (right sides facing). The ribbon is sandwiched between the two halves. Pin closed and sew along one narrow and one long side, leaving the folded narrow side open. Trim the corners to avoid bulky parts.

7. Turn inside out, straighten the corners with a sharp edge (I use the tip of a letter opener), fold in the narrow edges from step 2, and press.

8. Topstitch along the edge to close it.

9. Throw away the paper napkin, ticket, receipt etc. from your current book, and replace. Done!