I had a friend who went to South East Asia and I lent it to her. She said that she packed it along just because I suggested it. However when she got there having that little layer of home between you and questionable sheets made the difference between a good nights sleep and bed bug paranoia.
Step 1: Sew the Edges Together
Step 2: Customization
You could make it fancier by putting a drawstring on the top.
Making more of a mummy bag.
Adding a pocket for a wallet/passport/ any thing you want to keep close while you sleep.
If you arent sleeping in it they also make a good laundry bag.
Hope that helps and happy travels.