Cleaning an orange seat

Having noticed a distinct drop off in performance of late I can only put it down to my orange seat gradually turning black.

What's the best way to clean the seat and restore it's original oranginess ?

Ta very much

Why you'd want orange escapes me, but... Try some foam shaving cream. That stuff works wonders on vinyl and the like. Strong enough form your pumpkin, gentle enough for your ol lady's cooter.