Toes. Try doing the walks on your toes as if you were wearing heels. Actually, you only need to raise your heels slightly, but it will give everyone else a laugh
You will also find that tilting your pelvis forward helps.
When ladies 'stalk', they are placing their feet in a line; one foot is placed in line with the next. The leg going infront will roll the hip with it, so that the hip 'walks' with the feet. Since you're male however; do this too much and it's "mincing" and you need to have your arms bent at the elbows with hands hanging limply.
I have no idea where "snake-hips" ends and "mincing" starts... I think that's a lady's call.