Here's the pattern"

1. Measure each side of your basket.

2. Math: add 1/2" to each side of your basket.

3. Cut pieces to the size of your basket +1/2" on each side. Use scissors.

Note: 1/2" is the 'seam allowance. When you put pieces together and sew them, they will overlap by this measurement and the size of your finished project will decrease by that amount.

4. Cut straps to desired width and length.

5. Sew straps into top of bag.

This is completely not rocket science. If I can do it with a Right Brain Hemisphere made entirely of papier mache and budgie feathers, so can you.