[jveik]

well, some things are simpler than you would expect. i would try putting a good couple of coats of 3-n-1 (primer/surfacer/sealer) over your existing primer, though you want to scuff the original first with some 300-ish grit paper. then after you spray 2 or 3 coats of 3n1, let it dry at least overnight and then get some contrasting color and put just a slight mist over the entire primed area, not too much, just make it look like you oversprayed accidentally on it, or like there is some dust on it, just a little is needed. once that mist coat dries (takes about 5 seconds lol) you take some 400 grit wet paper, or if you want perfection, 600 or 800 wet paper and wetsand the entire car using a block to keep the paper uniformly flat. little areas that are curved or in corners, like door jambs can be done by hand without the block, just use your palm. the longer the better for the block if it is on large flat panels. basically, use the previously applied mist coat as a guide. you know you are done sanding when the mist coat is gone, as in you sanded it off... this allows you to see where you need to add glazing putty to low spots and also makes sure you have smoothed the entire surface to be painted. after this, use a garden hose and a paper towel to clean off the sanding sludge/residue. just make sure to wipe every square inch and wring out your paper towel often. if you miss a spot, you will be able to see it when the water dries and can get it then. after this, make sure there is no grease or oil from your hands on the surface by wiping it down with shop towels and a pre-cleaner... make sure to be sure it is a cleaner that will not leave any residues. usually paint suppliers sell "wax and grease remover," which should work fine. after that, mix your color and before spraying, wipe down the car very gently with a tack rag. if you press the rag against the car, it will leave residue, so just let it slide along almost like you're just dragging it along the surface. then go ahead and shoot the color. if, and only if, it is a solid color, when it sets up good, you can use 1000 grit or higher wet paper to take off any dust nibs and whatnot, then shoot the clearcoat over the color. make sure not to wait too long after spraying the color to spray the clear, or it might not stick very well. the clear will have an orange-peel look to it (look at any factory clearcoat finish and you will know what im talking about) and if you dont like that, then put on many coats of clear so you can buff it later on to make it perfectly level.

you can do the masking you described of the garage, but on a calm day it is not entirely necessary. i just wet down the garage floor, the driveway, the lawn, and any bushes nearby, and the frame of the garage door, to drap dust in the water. this really works pretty good, just get a decent sized fan to blow overspray out of the garage or the paint will look like little pieces of sand were sprinkled on it and you will be mad lol... ive done it before, not fun at all to sand again and redo it