Here’s something I found on the internet. Don’t know who they are otherwise I would credit them.
This is the WRONG way to do it. This is shown first because this is what people usually try to do initially and wonder why they’re failing.
First Foot: First you put all your weight on the ball of your foot you intend to keep still. Then all you do is slide your other foot backwards ON THE HEEL. I repeat, KEEP THE HEEL ON THE GROUND. Note: You should be able to move your 2nd foot freely without hindrance. You should be able to move this foot along the ground easily without it getting stuck. If your foot keeps sticking to the ground or getting caught because you put too much pressure at the last second, keep practicing just balancing on one foot while sliding your other along the ground without effort. You’ll get it eventually.
Shift the feet: Now, switch the position of the feet. This should be a rapid movement. In a split second, pop your 2nd foot up and shift all of your weight onto its ball just like before (Not the heel!)
Second foot: Since all of your weight is now on the ball of your second foot, you should be able to move your first foot freely. JUST LIKE BEFORE, SLIDE ON THE HEEL OF YOUR FOOT. NOT THE BALL. Sliding on your heel is what gives the illusion you’re looking for. If you have a hard time sliding it along the ground without getting stuck, keep practicing just shifting your weight onto the 2nd foot. The shift should be almost instantaneous. Remember, do not apply pressure onto your moving foot. You are entirely balanced on your standing foot.
That’s all! Just repeat the previous steps and you’re set!
Now onto some details that matter.
Length Matters: The first detail is the length of your strides. Many people have short strides when they first learn this. This is okay and it still looks good, but if you want to do a more Michael Jackson-esque moonwalk, you have to lengthen the distance between your feet during the strides.
Proper Stride Length: The best length is essentially the distance you naturally have between your feet when you walk. Take a few steps and note how long your strides are (don’t force it to be long or short here now that you’re actively thinking about your stride length). Walk to a door and just stop midway through a step. Look at the distance your feet have between each other. This is how much you want between your feet when moonwalking.
Flow: You might notice that the shorter stride may have looked smoother than the longer stride. That’s because I kept my upper body moving at a constant smooth movement. Try to keep your upper body moving at a constant speed backwards and without bouncing. This is what you get when you follow all of the instructions. Enjoy!