First of all, learn the purpose of each knife and always use the right knife for the job. Don’t try to cut that fresh loaf of bread with a carving knife when you have a bread knife in the rack.
Prior to each use, check the blade and sharpen as necessary.
After each use, wash and dry your knives; do not allow them to drip dry. Water and moisture will dull a knife.
Always store your knives in a butcher block or sleeve. Letting them rattle around in a drawer is a sure way to dull them.
Tell others using your knives that they are SHARP.
Do not put your knives into the dishwasher. Even though they may be “dishwasher safe,” the blade and handle will be damaged over time. Also, the dishwasher drying elements are very hot and if a plastic or wood handle should fall on one, smoke and excitement will ensue.
Resist using the blade of a knife for purposes other than what it is designed for, such as prying apart frozen meat. Knife manufacturers will NOT replace a knife with a broken tip. Instead, use a flat screwdriver (not a Phillips) to pry apart those frozen steaks.