This is just an idea, I'm not a pro. I woud work on turning the with the dog at heel. If the dog is on your left side, start turning with the dog on your left side. Start putting your knee into the dog to get him to move over alittle. Mix up when your going to turn so the dog does not know when you are going to turn. Just alittle knee bump with HEEL and that will get the dog out from under you.
I like to use food rewards for the real little ones. It keeps there focus more on a handler. Take a few steps and offer a treat. "Good ... Heel" then a few more ... administering a treat all the while moving along slowly. Do this on both left and right sides.
Also - start with pup in front sit (HERE) position. Use your treat to lure to either left or right side and encourage "heel" position. Teach that "heel" is a place next to your side weather moving or stationary.
I find that when dogs are very young less presure more direction and praise works for these types of basics. Pups tend to be ALL OVER the place under foot ... move slowly and delibrately. Most dogs are food motivated so use that to your advantage to keep focus and make the pup aware of what he / she is doing with his / her body.
Just walk with a normal gait. The puppy will learn his or her place once he starts getting clipped a few times with your big feet. Notice I didn't say kick the dog or hurt him. Just make him want to walk somewhere else other than under your feet.