Once the second layer of plaster has completely dried, use 150-grit sandpaper to sand down all the rough spots on the plaster surface. Make sure you hit all the edges and get rid of lumps.

Plaster is making a huge comeback in every way, but this trend goes way beyond the plain old plaster you might be familiar with. We’re seeing textured plasters used on walls, kitchen range hoods ...

Use a paint scraper made for exterior siding to "V" out the cracks. Fill with a quick-drying, nonshrinking patching plaster. Sand lightly, prime, then paint.