Four (4) simple steps should be followed in preparing paint, either for spray, brush or roller applications:

1) Thoroughly stir or shake the paint. A power driven shaker is very helpful. The continuous stirring or agitation of the paint result in a uniform mixture of pigment, binders, and thinners. it is very important to stir paints, most especially primers, well because of their heavy pigment content. Insufficient stirring most frequently causes paint film defects and color matching problems.

2) Reduce with the right type and correct amount of thinner or reducer as recommended by the paint manufacturer. Always keep paint and thinner at room temperature. Do not use "low cost" (cheap) thinners for high quality paints. Avoid using high cost thinners for the wrong paints, such as lacquer thinners for enamel.

3) Always add thinner slowly to the paint with constant stirring.

4) Strain the reduced color or clear topcoats through a fine mesh metal or commercial cloth strainer. A 100 mesh screen (100 parallel wires to an inch) is good enough. Use a course screen (50 mesh) for all primers. Built-in paint strainers are available on modern spray guns, eliminating the necessity of straining the paint before inserting in the gun cup.