I'd like to give credit where it's due but alas I can't recall where I saw the inspiration for this look. It was just too fun to not give it a try. Once my nails get a bit longer (since you need a bit of room to get all the colors in.) I'm going to give it a whirl on my own.
Step 1: Take your yellow polish (China Glaze 'Solar Power') and with a sponge apply it on either side of the horizontal center of your nail leaving a blank space in the center.
Step 2: Take your blue (China Glaze 'Shower Together') and with the sponge apply it to the center and extend out about midway into the yellow.
Step 3: I wanted to pump up the brightness on the green that was created by overlapping the blue and yellow so I took some Pure Ice 'Wild Thing' and sponged that over the top.
Step 4: From there I took orange (Sinful Colors 'Patrika') and sponged it out to the tip.
Step 5: Being careful not to cover all of the orange take some gold (Orly 'Glitz') and sponge to the tip.
Step 6: For the final bit of color take some brown (China Glaze 'Unplugged') and sponge just the very ends of the nails.
The base color is now done. Pretty cool huh? It looks a little rough but your top coat will take care of that.
Step 7: Now, with an unsteady hand (Yes you read right, it looks better if your a bit shaky.) start to draw in your lines. I used Stripe Rite black but I've used a black sharpie before and it works ok. Keep the lines irregular in shape and length. I alternated sides.
When you're done it will look something like this. Nice eh?
And finally, add your topcoat (Orly) ***Note: I had a bit of an issue with the stripes smearing vertically at the tips and making it look all wonky when I applied the top coat as you normally would from the nail base to tip. To keep this from happening apply the first coat horizontally with the stripes, that way if it smears it doesn't matter.
This picture is showing one coat so you can see how it's smoothed things out and brightened them up. I'd recommend a second coat though since you can still see a bit of the roughness from the sponge technique.