Glad you asked...
If you get lost in the wilderness, you can easily make yourself a bola. You only need a few things. You need rope, a knife and three round rocks to make a bola. See this site for complete directions for making a bola. http://www.ehow.com/how_4423022_make-bol...
Then again, this answer might help you...
Bola's are very easy to make. It's three sections of rope tied together, with the other ends made into balls. Inside the rope balls are weights. The bola is thrown at an animal, wrapping around the lower legs, causing the animal to trip and fall.

