That's all, you're done! From here on out, your strings will not get pulled out. I don't know how giving credit has to happen, but the only other time...
Some people have an odd sense of humor. Some people find it funny to pull out other people's sweatshirt strings when their not looking. Being in Middle School, this is an extremely prevelent "joke". I love wearing Sweatshirts, especcially ones with strings. In this instructable I turned one of my marching band sweatshirts into an "un-de-string-able" sweatshirt in a few easy steps.
Step 1: String the Sweatshirt
Take a string that you like (I used a golden one from an old sweatshirt that I liked) and thread it through the sweatshirt.