The reasoning here is simple. Every color in the visible spectrum can be assigned a number based on a luminosity scale (a scale from light to dark) from 0 to 9 where white is 0 and black is 9. Now suppose that the brown you are trying to cover has a score of 8, and the yellow paint you want to apply has a 4. Remove side view mirrors (unless they're to be body color) as well as exterior door handles and locks. This will take some extra time because you need to remove the interior door panels to get these off, but it's worth it. Head lights, tail lights, marker lights and license plates should come off too, but you'll need them in place to drive to the paint shop. So bring some tools so you can quickly take these off once you arrive. Depending on the year Mustang you can just take off the chrome bezels or rings. The shop can then easily mask the headlight or tail light itself and still get plenty of paint around the edges. Choose from historical hues for period homes; sleek chalky finishes that stand up to the rigours of modern life; or new formulas designed to suit all surfaces. By understanding the product you can unleash all the design possibilities of paint that make it such a tempting medium.
Airless Tip: If you have somebody who can start masking off the trim, have them start on that while you convert the airless to a new color. When changing colors with an airless paint sprayer it is a good idea to have a second bucket filled half way with clean water. Place the intake hose in the clean water gently without getting the old color everywhere in the water. Take the tip out of the airless and spray all of the old paint out of the hose and back into its original paint bucket. Be careful when doing this that you recognize when the paint starts turning watery. When it does point the gun into the first bucket and spray until it looks pretty clean. It doesn't need to be perfectly clean. When it looks good, clean off the intake line in the clean bucket and get the old color off the intake line. Now place the intake line inside of your new trim paint. Step three: go online and study the basics of shadow and light. It's a visual thing, and too complicated to talk about here. But once you see it, it'll come to you quickly. Simply Google "shadow and light in painting" and the basics will come up. Once you know these rules, you can apply it to any shape, any form, any painting. And it'll make you keenly aware of shadow and light on virtually any object on earth. It's what makes a painting three- dimensional and expensive looking. You can also buy art books on shadow and light at any bookstore. But make sure you sit down for a couple of hours and study it. It will come quickly to you, I promise. 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. Masonry paints come in a wide variety of finishes, from textured to ultra-smooth. Opt for a texture if you need to disguise fine surface cracks. If you favour traditional finishes, then consider limewash, which is available from specialists such as Francesca's Lime Wash. The beauty of this paint is that it will mellow and weather with time. However, do check with the supplier first to ensure that the surface is suitable for this finish.