Much of this may be a no brainier to you, or may not apply to your project. I figured it could refresh your memory or help others that find this and want to do something similar and have never painted anything before.
Wash the entire car and let dry before you start your project, ( handling dirty parts will cause scratches )
Tape off anything you think could get scratched while removing the parts.
I use 2" blue tape when I can, and a layer of gorilla tape over the blue tape,
Using the blue tape on the first layer makes taking it off easy. Just do not leave the tape on too long or let it sit in the sun with the tape on it.
Do not try and remove or reinstall the bumper yourself, have two people help you if possible.
Take your time during the project, have safe places to put each and every part after they get removed from your car.
Have a clean work environment, if your going to paint the parts at home wet down the driveway,the grass anything that would be the source of dirt or dust getting in your wet paint.
Do this even if your painting your parts in your garage.
Do not have your car anywhere nearby while painting, make sure the car is parked up wind just in case.
If your going through all this hassle to get a professional result do not buy cheap paint.
look into Eastwood or similar companies they have many good quality and durable paints for your project.
http://www.eastwood.com/paints/automotive-finishes.html
Eastwood can load spray cans with professional paint so you can get a quality finish without a compressor, spray gun, filters regulators,hoses etc.
Buy extra paint so you can practice on something other than your car parts.
Pay attention to the temperature and humidity, if it is too windy or too humid or too cold, just do not paint the parts wait till the time is right.
Professional mixed paints can be custom tailored for your planned temperature range that you know you will encounter when painting the parts.
make sure to clean the entire part front and back.if you have dried up dead bugs and tree sap road tar etc on the parts use the proper chemicals to remove them do not be tempted to just sand it off.
Follow the instructions supplied with the paint, Read the instructions online before you buy the paint this way you know if the paint is right for your project and you will also know what if any primer or sealer you may need for the project.
Do not paint in direct sunlight. if you do not have a garage find a spot on the north side of your house to do the painting, when the area you want to use is completely shaded.
Have a sturdy place to support the parts your painting.
taking the time to make a rotating jig so you can move the parts around to get a smooth even finish from any angle is especially handy when working with spray cans.
Make sure the part has been properly sanded and prepped for paint, use the correct primer and paint for the material your painting, You don't want it to just flake off after a few months. Do not forget wax and grease remover. I use the wax and grease remover before and after sanding. also use a tack cloth just before spraying.
Make sure when painting any small part like this, spray before you reach the part and go beyond the part so each pass is even, if you start and stop on the piece you will get runs and a uneven coat. use the distance and overlap specified by the instructions.
If your using a spray can, a cheap one or one you buy from Eastwood shake the can thoroughly. I am pretty sure you cant shake it too much.
Have a good respirator that will protect your lungs, hang a sign or warn anyone in your home to stay out of the area until your done painting and the paint is completely dry.
Once you have the parts painted and looking good, take the time to clean the normally hidden areas of the radiator core support.
Cover the entire car with a plastic sheet to avoid over spray,Mask off the core support and anything you do not want painted clean and prep any part that you do want painted. repaint the front side of the radiator or AC condenser and any part that looks bad or will cause rusting problems later.
Replace or remove, clean and paint any rusted nuts bolt and washers. ( look for these rusted fasteners before you take anything apart If possible )
have the new fasteners on hand before you start your project.
Source any odd or hard to find fasteners with correct parts do not just get them at a home improvement store, take the time to find a Automotive fastener company like
http://www.automotivefasteners.com/
Clean prep and paint any and all brackets that you removed. You can even tape off clean sand and paint the back side of the bumper with flat black.
If you go through all of these steps, your project will look like it was done by a pro.
