All you need for this project is yarn and scissors. First, cut a strand of yarn slightly larger than your neck - it should go down just past your collarbone. Do this 35 times. Tie each strand in a circle - it can get a little tedious, but it's really easy to do while you're watching tv or something.
Leave 5 strands untied. Once you have the rest completed, put them together and then use the last 5 strands to tie the rest together. Space them out evenly around the circle and wrap them around the rest of the strands several times.
I'm thinking about making one with some chunky, wool yarn so that it'll be a bigger scarf. This project took awhile but it was really easy and incredibly cheap. Highly recommended!