I am still not particularly confident (perhaps this has kept me alive) in making left turns on busy multi-lane roads. I assume that the safest approach is to signal and change lanes when it is relatively clear and pray that the cars behind you will slow down or stop as needed to give you time to make the turn. Timing is key- you need to wait for enough of a gap to move over, but if you move too early, it's a problem because you are left exposed in the left lane. On the other hand, if you wait too long, you may have no opportunity to cut over if traffic volume is heavy. Then you are stuck having to go past your turn and make a u-turn or stopping and walking your bike across in the crosswalk.
Anybody want to share favorite tips and tactics for survival when making turns like this?