i did my mates, well he didn't colour code them , he did them gloss black on his silver saxo, i did that with a rattle can, and they came up mint, got a right nice shine on them
best thing to do is get a bodyshop to do it, but if you want to do it yourself, here's a little guide,
Take the Front and rear bumpers off, + the side trims. but you can leave them on,
Mask up, using masking tape and newspaper, masking paper
rude down with around 240grit - 400 grit, to give the bumpstrips a key, if you do them to smooth the paint wont stick, so 400grit is plenty,
when sanded, plastic primer them, allow to dry, then rub down with 1200grit, wet and dry, and make sure you really wet the sand paper, so then it will make them smooth,
do this around another 3 - 4 times,
when aplying the top coat, spray over with whatever colour, and leave to dry, and then flat it down again with 1200 wet and dry sand paper, but again make sure its wet, to get a better result,
Always flat the paint down between layers,
then when you have done the top coat,
leave to dry over night, and then lacqure in the next day, several times,
Jobs a good un
Adz