what and how is the best way to do gold swirl decorations around a fondant cake? please help.

Pipe with royal and paint, stencil with royal and paint or just paint on. You could also cut out fondant and paint.

I'm a messy painter and if I did it on the cake, I would end up with gold everywhere. I would cut out the shapes and paint, then stick on the cake.

Just make sure you just do a few at a time then stick them onto the cake. If the cake is round, and the swirls have to form to the shape of the cake, you don't want the fondant to crack.