Hi there! I've only just been breeding axolotls for a year now, but I've found it's both a lot of fun and work.
You'll want to keep about 20 eggs to rear yourself at most for your first clutch so that you're not overwhelmed but a bunch of hungry little lotls, and you can either freeze and dispose of the extra eggs or sell/give away the eggs. You'll find there's quite a few people looking for axolotl eggs generally speaking, and you can advertise them here on Caudata's For Sale, Giveaway, or Trade section. I'd recommend waiting until the eggs just start to develop before sending them to people though.
Selling the babies isn't terribly difficult, but can go a bit slowly so make sure you have room for the growing babies in the meantime. Again you can advertise them here and on other social medias. Shipping them can be a bit nerve-wracking, but isn't too bad. You can use either USPS or FedEx. Use styrofoam to insulate the shipping box and pack the babies in individual watertight containers (I personally use fish bags), and include a cold pack if needed. Babies need to be fasted for 2 days to ensure that they won't poop in transit and raise the ammonia levels, and they're good to go.
There are a lot of great resources here for breeding and raising axolotls but more of my advice would be to use a hatching tray for bbs (makes it easier to separate eggs shells out to keep babies from becoming impacted), change 100% of their water every day, use a little bit of Indian almond leaf to prevent infections, and keep some medication like Furan-2 (use in VERY small quantities only if absolutely needed) on hand just in case.