I would go with either edible glue or piping gel on the cake wherever you want the sprinkles to be and then press on over a wide pan (so you’ll have less of a mess) wherever you want them. Personally I prefer edible glue, but most will probably recommend piping gel. As to painting, if it’s a large area I would go with some sort of sponge. Best of luck and most important: Have Fun!!
The Garden Baker
