Got a ding in an a ceiling tile? For holes the size of a pencil eraser and smaller, repair them with white flat latex caulk. Don't use silicone! The shiny caulk will stand out worse than the hole. 

FAST CAULKING: A common mistake is to cut off too much of the caulk tube tip, leaving a hole that is way too big for most interior work.  Instead keep the hole tiny...maybe 1/16",  so that you will have just enough caulk for small to medium sized cracks.  Use a second pass or have a second tube with a larger hole handy for the wider cracks. A quick swipe with a wet fingertip and you'll be paint ready!

Drop Cloth Substitute: Dropcloths can be a hassle.  They slip on hard floors, get bunched up under ladders and are difficult to fit tight to baseboards.  Eliminate the hassel and save time by buying a roll of rosin paper at the home center.  They come 160' long by 3' wide. Roll out, leaving a 1/2" gap from wall, then tape down with blue painter's tape.  Voila! 

SHED RESISTANT ROLLER COVERS: If you're picky about how your walls look when you're done rolling on the paint, then you'll want to avoid leaving a trail of roller fuzzies behind. Look for rollers labeled "shed-resistant woven." They cost a little more but the smooth, lint-free finish is worth it!  Don't forget to lightly sand the walls before you start to remove previously imbedded lint, dirt particles, pet hair and the like from your last job before you learned the "Pro" way of painting.