If the surface has any small gouges or nics they show up big time. Sanding has to be done to remove even the smallest of tags and blemishes. You need to find a paint man and get him out for lunch. Let him do it as a side job. They got the real paint and you can always make him do it over.
Do it right, do it once.....
I talked to my paint man and Nov he will do the bowtie, upper and lower plastics on both the front and back bumpers in white for $150. Gives me time to save up and gives me time to get more for the same price. Really I will stop there... no, really...I mean it.....