K.S.
Just a couple ideas:
Try putting his clothes in the dryer for a few minutes and then tell him they will be nice and warm/cozy if he puts them on really quick (my 4yo loves this on a cold morn).
Use pictures velcroed on a chart (hang on a wall or doorknob). The pictures should show each item of clothing individually and can be stuck on the chart in the order he wants to put them on. As he does each one he can take off the pic.
My SIL uses a reward system. She pays her twins a quarter each if they can get dressed for school in the time she sets. Works great for them.