It really is a case of practice, practice, practice.
When I started wearing heels it was a pait of spanish leather slingbacks with a 3inc slim(but not stiletto) heel and I was initially very wobbly. I soon got used to them and could even (girly) run in them. I then progressed to a pair of Mary/Janes with a 3 1/2 heel then on to a pair of stilettos with a 3 1/2 heel. The more I wor my heels the better they fitted and the easier it was to walk in them. I can now wear a 5 inch pair of courts with a stiletto heel without issues. As has been mentioned ones posture is a big thin and it is kind of easyer if ne inces rather than trying to take giant steps.
Whiost heels are not always the practicle answer, and after they have been worn for a while, the kill ones feet. This is all worth it for what they do to the calfs and derriere and how much more womanish ones movement is when wearing heels.
Take care girls