Clean off nails using the polish remover. Then rinse nails with water (don't use soap!)
Start by applying the tape to whatever thickness you wish to have your french tip to be
Next add a coat of clear polish to your tip..
Shake off loose sparkles.. Let the polish dry..then add another clear coat to the tip. Securing the sparkles in place. Let dry.
After polish dries over the sparkles... Carefully remove the tape.. Should reveal a perfectly lined sparkle tip
Finally cover the whole nail with another clear coat to finish the nail off for a clean look.
You may use this strategy with nails that have been polished with a base coat color. Just make sure that the base polish is completely dry so the tape doesn't take the it off.
Hope you enjoyed this tutorial! Good luck!