OP, just keep climbing and you will figure out what works best for you, as long as you aren't hurting yourself. It's generally agreed that a higher cadence is easier on the knees, but ther are mashers who do quite well.
Most of us remain seated for most of the climb, but there are those who stand a lot. I climbed a 9 mile canyon here with a guy who stood the entire way, and he was no light climber.
I also rode 10 miles across the valley with a pro who stood up the whole time while I was red-lined.

forgot to add, be sure you have a low enough gear if you are doing any sustained climbs. I climb about 300,000 feet per year and I'm old and fat so I use a 34x29 low gear.