8. Once you're happy with it, wash everything down with a sponge, remove any excess powder and otherwise get it nice and clean. Wait until its dry as the next step is the painting.
9. Its up to you how you wish to do the final finish. If you've done an excellent job with no obvious lumps or indentations, a good spray painter may be able to respray just that section for maybe $50-100 and it might come up as good as new.
Generally I've just used the "touchup paint" method. As knowing me it won't be long before i had to do it again. Go to an autopaint wholesaler closer to you (use yellowpages!). They are the guys that supply panel shops and the like with all the raw paint, etc.
Ask them to mix up a 50ml or so bottle of "touchup paint" for your paint code. To find your Nissan paint code and, just do a search on here, or how to find it on your chassis plate. Just explain what its for and they should be nice and mix it up for you for around $10.
10. Generally the bottle will come with a paintbrush in the lid, or you can choose to buy some decent fine brushes for $5 or something to do the job a little nicer. '
Shake it up to mix it well, and start painting over the repaired area! I've found long smooth strokes is best so that you don't get too much rough bits. With my job its kinda a "2nd used" bottle, so had become a little gluggy which didn't help me get a perfectly smooth finish - so when i get another fresh bottle may try again.
If you end up with a poxy job you're not happy with, the best part is you can get out the sandpaper, sand all the paint off in a minute or so, and try again.
This should be it. Let it dry and all is done. Attached are the results of my fix-it.
The bad news: from 1 metre away or so so (as shown), its going to be noticeable and you're always going to know where to look. On casual inspection or anything other than total brightness probably others aren't going to notice. You'll never get it "perfect" but at least it won't stick out like a sore thumb, and its not going to crack further.