The best way to build a Towel is to do it with Brooklyn Aerodrome. The process is for you to get the radio gear/plane parts and we provide a parts kit for $20. The Towel takes around 3 hours to build if you have help from someone who has all the tools/parts and knows how to make the parts. The plane flies well and easy to repair. It's major parts are the deck, the towel airframe and optional lighting for night flying.
The goal of all this is to make one of THESE:
There are many ways to create towelness, this document presents a few of the ways but feel free to improvise with what you have around. There is a video of us building a Towel if you want to get a feel for the process.