1. Get focus with the centre AF point
2. It takes about 0.5 sec for AI Servo to lock on, so either the first shot is OOF or wait 0.5 sec before taking first shot, either way it's OK.
3. Keep at least 1 cross type AF sensor on the subject at all times (not sure how many cross-type sensors and which one the 30D has). This works better if you keep the centre AF point on the subject at ALL times.
Do not expect every shot to be perfect, AI servo is good, but there are limitations.