Painting with a roller.

On most of the interiors, painting with a roller preferred over spray painting. Spray painting would work on interiors better, if the house is unfurnished, it is a complete painting job (means doors,trim,ceilings,closets,baseboards included) and it is all one color. Or if there is a popcorn ceiling, it needs to be spray painted. In all other cases painting with a roller would be a better choice.
The fastest way to paint with a roller, if the large surface is painted one color, is to use a five gallon bucket, filled with paint in half and a roller grid. Prior to using a roller all the lines(corners, around windows,doors, lines between ceilings and walls,etc) need to be painted with a brush first. If you leave 3-4 inches strip of paint with a brush that should be enough not to leave marks on the ceilings, door trim and baseboards, when painting with a roller. If the strip of the paint that is left with a brush is too narrow, you will accidentally touch the areas that you not intending to paint(ceiling is the most common place to see the unintended roller marks left by beginner painter).
If glossy paint is used, the strips cut in with a brush, need to be overlapped before they get dry, in order to hide the lines between ares painted with a roller, and areas painted with a brush. It is called to keep a “wet edge”. That is why for beginner painters it is recommended to use paint with a low sheen.
Prior to rolling one needs to choose the roller cover that suits the surface. Most drywall in Arizona is textured, so the roller cover for rough surfaces would work well (sheep, or lamb skin is the best). The appropriate roller cover will allow you to paint at least 2-3 lines in the room 8 feet in height, without dipping the roller in paint. If you painted one line and roller cover already needs paint-you picked the wrong roller cover.
When starting to roll, it needs to be done from one corner of the room to the end of the wall. You start from the dry area and paint towards the wet area overlapping strokes.
First stroke on the wall should be upward, as pushing down on the roller full of paint may cause dripping. Paint lines need to be from the top of the ceiling to the very bottom, always keeping the even pressure. For that roller extension always need to be used . Painting only with roller handle will bring poor results. Only minimal pressure needs to be applied at all times. If roller cover is running out of paint, no need to apply pressure, trying to squeeze one extra line. It is time to deep the roller in paint again.
If the paint doesn't come off the roller cover easy it may be because the paint is too thick. Thinning down the paint with half a gallon of water on five gallon bucket may give better results. No need try to achieve perfection with a first coat. If paint is applied too thick it may ”run” and leave ugly marks. For most paint jobs two coats of paint will be needed (that is unless you are color matching an existing color). Most of the paints dry up pretty fast and second coat can be applied in 1-2 hours after the first coat. In closed up areas (bathrooms, laundry room) paint may take 3-4 hours to dry.
Prior to using a roller the best way to prepare for paint spills is to spread painter's plastic. Run 1.5 inch painter's tape along the baseboards and tuck in the plastic under.