Use a French-filled diamond bit, carbide straight barrel bit, or specialized backfill bit of an electric nail drill during this process. Backfills should only be done along a client’s natural free edge. 

1. If you’re a beginner, then use the inside portion of a nail form and a pencil to draw a smile line. Use this line as a guide for where to drill on the nail.

2. Using a speed between 5,000 to 9,000 RPM, position the hand at a 10-degree angle and cut a new smile line. White acrylic dulls in color as it ages. The new white tip powder is whiter and will make a strip of lighter white if you don’t remove the entire white tip when doing your backfill. Remove a minimum of 80% to 90% pink and 60% to 70% white.

3. Instead of a diamond barrel bit, you can also use a carbide straight barrel bit. If you use a carbide straight barrel, start at the right side of the nail and go toward the left side, holding the bit parallel to the nail. Hold the electric nail file securely without too much pressure on the nail. Don’t cut too deep. You can go back over the area if your cut isn’t deep enough.

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