Apply painter's tape to trim and wall fixtures.
Lay a plastic sheet on the floor in case of accidental splatter or drips.
Trace your argyle pattern directly onto the wall surface using a pencil and a straight edge. The easiest way to trace the pattern is to copy images of argyle patterns from the Internet or a book. With a scanned book page or Web printout, convert the pattern into a slide or transparency. Use a projector to display the image on the wall, then trace its outline. If you don't have access to a slide-show projector, you can use a tape measure and protractor to plot and trace your pattern. A basic argyle pattern is just a series of squares turned sideways to form diamond shapes. For good squares, measure even line lengths and ensure a 90-degree angle using the protractor.
Apply painter's tape over the pencil marks in a crisscrossing diamond-like pattern.
Paint your argyle diamonds with a flat latex paint. Use a 2-inch paintbrush for edges, and a paint roller for larger wall surfaces. Argyle patterns always feature at least two different colors, alternating between each diamond shape.
Apply a second coat after the first coat dries for 2 hours. Wait at least 24 hours for the second coat to fully cure.
Remove the painter's tape, revealing the crisp argyle pattern beneath. Erase any leftover pencil marks.
Apply painter's tape parallel to the newly painted edge of the old painter's tape marks. Your goal is to get rid of the unpainted, blank surface leftover from the painter's tape. Ensure the new tape lines protect the painted wall for a crisp edge, while still giving you access to the unpainted lines.
Paint over the unpainted wall portions with a 2-inch brush to complete the argyle look.
Apply a second coat of paint once the first coat dries in about 2 hours.
Repeat Steps 3 through 10 if you want to create additional, overlapping argyle diamond patterns.
Remove tape from the trim.