Wall painting is easy when done in the right sequence. Interior wall painting is done after all the necessary preparation work is done. This includes repairing cracks in the walls and around doors and window frames. Wall cracks are a funny thing, the crack could be larger in the wintertime or smaller in the wintertime as the house expands and contracts and moves around. To prevent this type of situation we always use drywall tape and plaster over the crack.
Generally speaking we put fiber tape over the crack which stays in place while you plaster over it. Don’t try to cover the fiber tape and crack open one plastering. Fiber tape has a certain amount of thickness as does regular paper tape, so you must make your plaster repair wide enough not to show a hump in the wall. Then you feather out the plaster repair transition into the wall.