Paint Job Help

I just got my 2006 Mustang and I want to do a two toned paint job on it. I'm going to use spray paint because I don't have an air brush. How can I stop the paint from bleeding through the tape? Last time I tried it, there was also a "crease" that stuck up where the two colors met. How do I get rid of that? Please give me all the advice you can.
Thanks

Spray your primer, mask off the first section and spray the first color. Wait 10 > 15 minutes and remove the masking tape, allow first color plenty of time to dry completely. Mask over first color, spray second color, remove tape as before and allow plenty of drying time again.

If same number of coats were sprayed for both, there shouldn't be a major step, light polishing should remove whatever ridge is there from masking.

Threads the search feature found when searching for 'two toned painting'

http://www.automotiveforums.com/vbulletin/showthread.php?t=247988&highlight=tone+painting
http://www.automotiveforums.com/vbulletin/showthread.php?t=227767&highlight=tone+painting