I usually will use Fondant Mats for my pretty soap tops.
I decided to try something new, a Hand Roller. This one is made of carved wood and came from an Etsy Shop with a nice selection, MKM Pottery Tools. Do check them out!
So after unmolding the soap, I gently rolled the tool across the top of the soap.
Here's the completed soap, I was pretty happy with it. Give it a try!