I have nails that crook downwardas they grow and I use a fairly common hot spoon method to straighten them every other day. The downward crook makes it difficult to get a correct shape, but also required a change in right hand string attack. I paid a well know teacher/player/performer to help me get both a correct nail shape and change my angle of attack. After an hour plus of minute adjustments the snagging of my nails against the strings stopped and my tone improved a lot. I had the teacher photograph my hand position and close-ups of the nail shapes from the top and the bottom. I can’t say that I repeat the shape exactly, but when I combine the hand position with nail shaping the results are consistently good.
I use two products for my right hand nail care that I bought at SBM. First, a Ruby Red Crystal File to shape and shorten and a micro mesh nail care kit. I never, ever, ever trim or cut a right hand nail. Even when I break a nail I use the file to remove the broken part.
I bought two spoons, one very small to insulate the flesh of my finger and one that is larger that I heat with a lighter and it’s that part I use to ‘iron’ my crooked nail. Not for the faint of heart, but it works.
Make nail care a daily habit. Your guitar tone will be happy.
Best of luck.
Hauser III 2014!