Sounds like your useing to much water and not laying on right, after frist trowel...When you square the wall up...All the hollows/miss's should be out.....So you don't have to use any fat to fill after it's picked up....If you wash in your angles to early it will look crap with brush marks.....You don't need t use much water at all really, unless your fighting with it....
How long have you been plastering mate? You ask a lot of these questions.....
