The weakest part of the blade it the tip. Look after the tip and the rest of the blade will last.
The steel I use is Stainless Steel not rust free steel. Keep you knife dry and it will not rust.
For long term storage store you knife with the sheath and not in it.
Clean your knife with a non abrasive detergent and dry with a soft cloth. Do not wash your knife in the dish washer !
Do not leave the knife in direct sunlight for long periods of time.
Blades with a bead/sand blasted finish can be wiped down with a little bit of WD40/Q20 moisture repellent spray.
Do not use your knife to dig, pry or chop. There are tools available for those tasks.
Do not use your knife as a screwdriver, the tip will be damaged.
Do not throw your knife. I do not make throwing knives, you can get them from flea markets.
Natural handle materials like bone, horn and wood can expand and contract with climate changes. The bone and hardwood I use is all stabilized and this should minimize movement.
Lightly wax your leather sheets, do not over wax the sheath as it will get soft.