Originally Posted by
RiPHRaPH
Try to alternately sit and stand while pedaling. Don't let your heart rate escalate too high too early in the hill. Don't get out of the saddle till you have to. Ride as you normally would, shift down (getting another cassette with a wider range of gearing is an easy, quick and cheap way to go also). Rise out of the saddle for a while (easy spinning, not all out) then back to in the saddle tilll you are up and over the top.
Keep your upper body quiet and do it. Change the formula for sitting and standing till you've got it down.
Adding to this, choose a taller gear when you're standing, then go back to a lower gear when you're sitting. When I'm standing to pedal, I like to use a gear that's tall enough to feel like I'm walking up a flight of stairs.
The caveat is that you'd need to accelerate a bit so you can softpedal and unload the chain to make the shift. If the hill is steep enough and you're already going slow, your momentum might quit when you're in the middle of shifting.