Start with shaped and buffed nails.
Clean nails thoroughly with acetone polish remover.
Do not use a base coat, as the blending for the ombré look will not work as well over a base coat.
Work with one nail at a time so polish is wet enough to blend.
Starting at the cuticle area, apply a blue polish in a thick layer, using a dabbing technique, about 1/3 of the way up the nail.
Using a lighter, metallic-blue shade, immediately polish, starting where darker blue ends, and "drag" the end of the darker blue polish up the nail to the end with the lighter blue to create an ombré "fade" (so the colors look like they fade into each other).
Continue this application with all nails. Seal nails with a quick dry-top coat.
Here is a great Tutorial. Hope you can try it... Really Nice Technique...