Raking your mast won't help if you are overpowered.

To depower, like Col said, use lots of downhaul. Also pull the outhaul out and if you are still feeling uncomfortable, centre the rotation.

When you've done all this the sail should be pretty flat. What sort of sail do you have?

It sounds like you went ok apart from the first capsize. How did that happen? Upwind or downwind? Sideways or nosedive?