Here is a simple design using a simple technique.
Start by painting all your nails, except your middle fingers, 2 coats of a gray polish.
I used Sinful Colors "Slate". Then paint your middle fingers 2 coats of a black polish.
I like N.Y.C. "Black Lace Creme" 119A.
Using a striper tool make 2 thick black stripes on your ring and pointer fingers. Then use a dotting tool dipped in white polish to create a heart on your middle fingers.