To use Shills Thread Cat Eye Gel Polish, start by preparing your nails with a base coat and cure it under a UV or LED lamp. Apply a thin layer of the Shills Thread Cat Eye Gel Polish and cure. For the second layer, before curing, hold a cat eye magnet over the nail for 10-15 seconds to create the desired pattern. Cure this layer under the lamp. Finish with a top coat and cure again to seal in the design. For optimal results, avoid touching the nails during the curing process and ensure each layer is evenly applied.