I guess I found out the hard way why a beginner power kiter shouldn't go out in high winds. Although fun, it was quite a struggle to hang onto a 3.3M kite in 25 mph winds and two days later I'm still sore.

The winds for the next few days look more suitable (10-15 mph). What tricks and techniques should I be practicing to get used to the kite? I know about flying blind (not looking at the kite), but is there anything else I should be practicing? How about bad habits I should be avoiding.

I've done a fair amount of reading but there is little information on what skills to learn first and which to build on.

Good call on the wind speed.
Really learn what the kite is going to do next in all conditions.
If you are planning to put yourself in motion on a board or buggy, learn kiteloops and learn how close to the ground you can pull them off in various conditions. They will be a a useful tool. While flying static, use them to extend your scudds.
Habits to avoid: Using body language to steer the kite. You've already learned to manage your conditions with high winds, just also watch out for storms, bad weather too.
Have fun