Check out the IV megathread...most of your questions will be answered there... as for a torniquet, you can use pretty much anything at all that is long enough to reach around your arm and the off. The purpose is simply to restrict blood from flowing out of the limb and back to the heart, which makes the veins engorge and swell...and therefore easier to hit....it's a very simple concept.
For the sake it HR, I have to add to think long and hard whether you really want to start IVing speed...particularly if (as it sounds) you have no experience in doing this...
Its not a good road to go down bro and I'm 100% certain nothing good will come of it and you'll regret it