I've mentioned how much I love shoes, especially if they are heels up to 3 inches.
I've been told I do such a good job at it I have had biowomen at various times pull me aside and privately ask me how long I've been doing it and how I learned to walk and stand comfortably in them.
First order of business is to make sure they are comfortable. I don't care if they are cute, the exact color I need for an outfit or on sale, I never buy shoes that are too small or too tight in the toe box for my feet.
Comfort is the name of the game, especially if they are shoes I'm going to be spending extended periods of time wearing, walking or standing in. I'm not shy about getting them a half size to a size larger in search of comfort.
Unfortunately, once you start approaching a size 9 and up there aren't in many women's shoe collections half sizes, so you have to go up to the next shoe size. You also want to start with a lower heel height and work your way up
As for what worked for me, before I even started walking in them I would get used to sitting and standing in them for extended periods of time. I'd get either an old pair of knee highs or hose and simply put them on. You especially need to do this with shoes that you've just purchased so they can mold to your foot.
Most of the time I'd simply just put them on and practice walking and standing in various heel heights. I had stairs in my old apartment and practiced slowly walking up and down them since one of my fave clubs back home had a stairwell I had to negotiate. You also want to practice once you get the hang of walking in a straight line in them on carpeted and non carpeted floors, stopping quickly and turning in them as well.
And yes, I even practiced dancing in them, too.
You want to make sure you're standing as tall and straight as possible. Since I have long legs, I naturally have a longer stride, but ideally you want to take short steps and land on heel first, then ball of foot while trying to relax your legs as much as possible to avoid getting cramps.
While there won't be any great high heel races in my future, over time I've gotten to the point where I can confidently and gracefully walk in them without a problem.