In terms of complexity, painting an interior wall may seem like an easy task that shouldn’t take you forever to accomplish. And while it is true that painting is definitely not in the same line of more complex tasks like electric work or plumbing, not every aspect of it is immediately obvious. You need to take your time and go through several steps, in order to end up with a result that is worthy of consideration. Painters follow certain procedures, which make their job easier and faster. Adopting their ways is a good way to take on this project on your own.
Procedures on Painting Interior Walls
The Preparation Phase
The first thing you need to do is to remove any obstructions in the room you are going to paint. This means furniture pieces and light switches. The more thorough you are, the more you will have to move around and do a cleaner paint job. If there is anything you cannot get out of the room, put it in the centre of it and just move around it. It is equally important to remove some small things, like light switches, outlet plates, hanging nooks and pictures. Place tape over the remaining components on the wall. There are certain obstructions that are very difficult to remove, like trim. It may be better to just mask off the trim, along with baseboards and crown moulding around the windows and doors. Prepare some white light, as it will later help you shine on the wall to get a clear idea of how well you are applying the paint.
Then, you will have to acquire some tools for the job. Start by getting the essential tools: extension pool, a ladder, work lights, brushes and rollers. The materials you should acquire include: primer, interior paint of the chosen colour, roller frame and cover, drop cloth/canvas/fabric for protecting the area from splatters, painter’s tape, gloves.
The Step-By-Step Process
Start by Applying the Primer
Not every interior wall painting project will start with primer application, namely when you are repainting a wall of the same colour or when the condition of the existing paint is good. But in other cases, you should use a drywall primer on the drywall paper surface. Pre-tinting the primer is something you can request from the paint store, in order to bring it closer to the intended wall colour.
Mix the Paint
Mixing the paint before you start is next. Use a wooden stirring stick or metal spiral power mixed attached to an electric drill. 
Start by Painting the Edges
The first thing you should paint are 4-inch wide swaths along the edges, painting alongside the painter’s tape. Apply at least two coats of paint.
Roll the Paint
Now it is time to roll the paint on the inner part of the wall. Dip the roller in the tray and squeeze it out. Put the roller on the wall and paint a ‘W’ shape, then fill the W to cover all sections. You should finish a section before you move onto the adjacent one.
Paint a Second Coat After the Paint Dries
When you finish a wall, wait a few hours for the paint to dry. If it is a glossy paint, it will require more time. Once the paint is dry, you should apply a second coat of paint.
Clean the Area
Clean the brush you have used for the job with warm water and remove the drop cloths. Let them air dry and store them away for second use. Pull the painter’s tape away.