It's a fools errand to try to do it your self. If you are not an experienced operator, you are better off hand held. There will be zero precision in your framing, and you'll be all over the place. Starting off with a low rent pos rig will only make it worse. Steadicam is a major commitment in time and money. I wouldn't expect to achieve any kind of semi professional results for several months (and that's assuming you are practicing 3 or 4 hours every day). I've been operating steadicam for more than 15 years, and thats my professional opinion.
Nick



