I was researching fingernail care for classical guitarists this morning and came across a nail-preserving trick on David Russell’s blog:
Tape up the nails. I use brown packing tape. The trick is to get the same sound as you normally get or at least acceptable and then be able to practice those extra hours.
Follow the drawings. Fig. 1, stick tape under nail. Fig. 2, fold over and stick down.
Check out the blog post for the diagrams and full instructions.
There’s also this blog post which containes some videos about fingernail care: