My son wanted to create the animal rescue center from Go Diego Go so I offered to make a hammock for Diego to sleep in. This guide shows a 9-strand hammock, but I think using 12 strands would make it a better width.
Step 1: Cut and tape the strings
I used 9 strings about the length of my arm - the size depends on the size of your doll. Unless you have a very patient and helpful young person to hold the strings, I suggest knotting the ends and taping them to your table. My son was anxious for the results, but not so helpful in holding things still.