Primer paints may be oil- or water-based and are used to seal unpainted surfaces to prevent covering coats of paint soaking in. The appropriate type of primer should be used for the surface being painted - wood, metal, plaster or tiles. There are some 'all purpose primers' available which are designed for two or more of these surfaces. Preparation, the key to a successful paint job is to take the correct steps when preparing the job. Preparation for this article, has two parts, the first part is wall prep. The walls you are going to paint may have nail holes or imperfections that need to be filled before you paint. The proper way to fill them, if they are smaller is with water putty, by simply forcing a little bit of the putty in the hole and breaking it off flush with the surface. For larger depressions, use a drywall compound or spackle, which may require a second application to fully fill the indentation and make the repair/"patch" flush with the wall. One precaution: You can't paint with it in cold weather. The chemical reaction that transforms the water solution into a durable finish will not take place if the temperature is below 50°. (Conventional oil paints don't stick well in cold weather, either.)
Materials and their application, every paint manufacturers paint will vary. If you are freshening up old walls and painting back to the existing color, the product doesn't have to be high end or have good coverage. If you need to paint a dark color over light color or light color over dark, you may want to consider purchasing a top quality paint to avoid multiple coats. I suggest Valspar, Pittsburgh or Benjamin Moore top of the line wall paint. These brands work well for straight out of the bucket use and are application friendly. Sherwin Williams is not my first choice because the coverage is poor and you will have to apply multiple coats but, it does apply, fluently. If you find a product does not apply well, maybe it is to heavy and/or sagging on the wall, you may need to thin the paint with a little water, this will reduce the coverage but make the paint flow better and lay down nicer on the surface. I do recommend latex paints for all applications, these days a good high end latex is as good as oil paint and your tools clean up much easier, it will also be less harsh on the respiratory system. The only situation I recommend oil paint, is as a primer/stain blocker over stains that "bleed" through the paint. You can get a stain blocking oil primer in a convenient spray can and spot prime any trouble areas before painting and in the case you need to prime all of the wall due to smoke or water damage, I recommend getting it in gallons and rolling it on where the stains are present. Don't forget proper ventilation and/or a respirator when using the oil based primers! You can tell when the bucket of paint is getting low when the airless starts pumping really loud and doesn't stop. Simply tip the nearly empty bucket of paint, at an angle so that the mesh filter is covered and wait for the airless to catch up and stop pumping. Sometimes it's just easier to just to replace the bucket of paint with the new one and when that starts going down, pour the excess from the old bucket into the new one. Thinking skills (cognition): Thinking is a kind of "inner speech". We talk silently to ourselves to think through things and solve problems. Children in imaginative play begin to develop this skill through talking aloud and explaining everything that is happening in the game. (Think of the children playing in the "home corner" in your playschool and how they tell each other what to do and talk to the dolls and teddies). Slowly, as they become more practiced, this talking changes to become "inner speech" (they think it but don't say it out loud). This is a major foundation for developing thinking and reasoning skills. A large whitewash brush is best for applying the wash. One should not attempt to brush out the coating, as in applying oil paint, but simply spread the whitewash on as evenly and quickly as possible.