Get yourself an ordinary sixpack of water, juice or whatever (sorry but beer won't do) and cut the handle in two halfs. Carefully tear of one half of your cloth.
Fold the non sticky part of the handle to stick to the glue strip. Use a puncher to make a hole to put the cord through.
We tried it and it
works all right!
Attach the glue strip to the back of your iPhone. It is best to first clean the iPhone with some glass cleaner to make the strip glue even harder.