Anchor your rubber legs, any barred rubber leg will do.
Move your thread to the head, it helps to do a quick half hitch knot.
Wind the leg material forward and secure.
When you start off give the the leg a good streatch, easing off as you go forward.
This will help taper the body.
Tie in the tag end behind the bead.
Double it up and do the same.
Cut the loops so they become legs.
Stretch them backwards, and wind thread towards back to secure them in the place you want them.
Leaving the thread towards the rear, dub it with some peacock colour ice dubbing or similar.
Wind the dubbing forwards, and finish up the fly.
Here are some variations, the second is using a darker material and no lead underbody.
As the flies get smaller you may want to substite the leg material for some fine wiggly rubber.