Some great tips on how to walk in high heeled slingbacks. You want to go back to the basics of walking in stilettos. Always start with your posture. Make sure that you have your head in line with your spine. Shoulders back, abdominals engaged. As you walk, you always want to be very conscious of your posture.
With each step, you want want to aim for the ball of the foot even though the heel will strike first. Try to find the rhythm in the walk, remembering that it is always heel toe, heel toe.
Some of the issues that women face when wearing slingbacks is pressure from the strap. What I recommend is getting moleskin. Moleskin is used by a lot of dancers and you can place it directly on your skin. It's a very thin layer, and it creates a barrier between your skin and the strap.
Women can also get a gel insert that you place in between that strap and your skin, which will protect it from creating blisters. If you notice that that back strap is slipping off with each step you take, the moleskin and gel insert will prevent that as well.