I used two polishes from summer 2012 collections: the green in "Citrus Blocks" (above) is Essie's Mojito Madness, from the Summer 2012 collection, and the white with a blue cast in "Hot & Cold Angles" (below) is OPI's My Boyfriend Scales Walls, from the Spiderman collection.
|"Hot & Cold Angles"|
For these last two designs, I used a smaller nail art brush or a striper brush for greater control and precision. You could also create these designs using tape. Apparently, the key to using tape and getting a clean line is to wait until the most recent coat is completely dry, apply the tape, paint the next coat, and immediately remove the tape (I have yet to master this technique). Check out the Nailside blog for some impressive tape manis.
When you're working with bright colors, starting on a white base makes the colors look brighter and more saturated. It might take two coats of white polish to have an even and opaque base. Try it and compare the difference; you'll be amazed.