I wanted to do a French manicure on my nails for a whole and could never get the white nail varnish perfectly curved or to look even remotely good!
I read a nail tip in a magazine, the magazine said to create the perfect French manicure... Use hole reinforcer's!
Start by filing your nail, I tend to file mine square to make them look false and perfect, but you can file them round if you want a more natural look.
Stick the hole reinforcer's just slightly below where the top of the nail has grown past the skin. Don't worry if when you paint it goes wrong you can touch it up using a clear varnish and a cotton bud with nail varnish remover applied to it.
Once the hole reinforcer's are on, paint the top part of the nail white, wait a few seconds then peel off. Do not leave for too long because the hole reinforcer will get stuck and create a jagged edge.
I've used BarryM white nail paint to create the French tip and then Ciate Underwear as the clear coat to make the nail shine but still look natural at the same time. The hole reinforcers can be bought from most stationary shops, I'd recommend WhSmith! But eBay sell them too!