The general rule is, in Ballroom, Standard or Smooth (whichever you call it), forward moving steps for either Ladies or Gentlemen should be heel leads.
But how to do a large step on the heel lead without my heels sliding out from under me? Easy! Keep your body weight over top of your foot, rather than behind it. The best way to do this is to have a slight bend in the knee that is traveling forward, and push off with the foot that is behind.
The Gentlemen's steps for example, would see the man having both knees slightly bent, the left foot moving forward, and the right right leg pushing the body into the step. If you keep your left knee slightly bent, you will land with the heel underneath your body, and no sliding. Same for ladies!
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