The key to making sure your at-home French manicure doesn't go awry is the top coat you use. Ideally, you should use a quick-drying top coat when creating any type of design on your nails. This ensures that, as you apply it, you won't move the precariously placed polish to other parts of the nail, and it also ensures a longer-lasting manicure. "Maxus Nails FINITO top coat is a fast-drying formula that's ideal for nail designs [as it] doesn't drag polish during application," nail technician Dasha Minina told InStyle. However, there is a wide variety of top coats on the market, and all of them can also help you extend the life of your manicure.
If you're still afraid of smudging and dragging upon applying your top coat, you might want to consider using drying drops. These products can be used on your nails after you apply polish, but before you add your top coat. Just a couple of drops on each nail is enough to speed up the drying process by up to 15 minutes, per Nails Magazine. This might be able to give you the peace of mind you need to apply your top coat without panicking.