I've got chronically ingrown toenails. How do I stop this once and for all?

In office procedure. This is generally an in office procedure. The toe is numbed with a local anesthetic and then special instruments are used to cut out the ingrown portion of the nail. Depending on the status of the ingrown nail (ie infected, chronic, etc) a permanent ablation of the cells that produce the nail to that side may be considered.
See doctor. The edge of the nail that is ingrown can be permanently removed and causes little to no cosmetic change in the nail appearance. Its not very painful-don't worry.
Get rid of toenail. You develop due to wearing narrow shoes, once ingrown part of the nail excised, matrix at the edge is cautarized it should not recur most likely still using narrow shoes, switch to wide toe box shoes. If still have problem removal of nail along with entire matrix may the answer then you will not have nail.