BASIC DRILLS
This list will grow but here's a few basic examples/drills for us old guys who learned the wrong way - to take off under and drive the bottom.
Attack the pole @ 90 Degrees - not leaning away
If a pole weighed 200 lbs, you could only get it to vertical by pushing at a 90 degree angle - Do the same with a small pole
Take off bounds make you jump up AND out
DON'T grab the bar. The objective is to put pressure on your hands and keep them ahead of your hips.
Jump/hit plant drill to learn pre-jump
You're in the air before the pole hits the ground. If you don't reach up or if you lean away, you fall on your back.
Two step straddle - push up/jump up into take off
If you can't straddle you're leading with your hips and not your chest. Keep the hands moving!
Four step slide drill extending up pole
Sliding the pole from a close run makes you jump up when you push your hands up.
Same drill with 6 steps carrying the pole - left leg up pole during extension
Swing in one motion. If your left leg can go up the pole you are vertical and less likely to flag out.
More on this extension drill including getting started