Just did this manicure this afternoon, I loved how it turned out. Believe it or not it's really simple.
Just put a white base coat on until opaque, then, using 3 colours of your choice paint random thick and thin lines on the nail. To make it easier I used my nail art pens.
Then, using a black striper, add lines and details for that tribal effect!
Have a good, it's good fun :) xx