Here is a useful website, also try searching on google and you tube for "DIY steadicam" or anything similar. My roommate and I just made a real decent one for about 20$ with supplies from home depot. We used this youtube video but for some reason when I go to watch it now it says I need a youtube account which I don't have but see if this link will work for you, this video was very helpful!
if you still can't figure it out send me a message and I will send you photos and dimensions of our stabilizer! Good luck and have fun with your macgvyer'ing skilllllz!!