I did it myself. It's not that hard, especially if you have big veins. The trick is to stab in there pretty quickly. If you are squeamish and try to do it slowly (which you probably will the first time), it makes a mess as the blood flows around the angled (beveled) point in the needle.
The needle is special. It has a bevel and an additional hole in the side for extra flow (or at least that is what I think it is for).
You have to stab that puppy into the vein pretty quickly, then no mess.
Go in at an angle, and then straighten it to follow the direction of the vein, then tape the tube down, then let it flow.