Open the panel door and stand where you normally would. Read the labels from there. If you cannot tell which breaker feeds the kitchen, the panel is still working, but it is harder to use in a hurry. That is an owner task. You can handle it on a calm day with a pen, a card, and a few minutes.
Clear the working space
Check the floor in front of the panel. Remove stored boxes, shelving, and anything that leans against the door. Make sure nothing hangs into the path the door swings through. Keep the area open at all times, not only when you have a reason to go in.
Check the labels against the circuits
Pick a few circuits you use often: the kitchen receptacles, the main bathroom, the laundry, the furnace or air handler, and the outdoor lights. Switch each breaker off, walk the house, and note what goes dark. Write any difference on the directory card. Do not guess. A wrong label is worse than a blank one.
Keep the card current
Each time an outlet is moved, an appliance is added, or a circuit is split, update the card that same day. Initial the change so you know who made it. Keep a copy with the other house records.
Know what labels cannot fix
Labels do not repair a panel. If you notice a breaker that is warm to the touch, a burning smell, a buzzing sound, scorch marks, or a breaker that trips again as soon as it is reset, stop using that circuit and bring in a licensed electrician. Those signs call for a visit before the next walk-through, not after it.
Plan the panel by its age
A panel has a typical service life, and its install year is a planning input. The Electrical Panel page on this site turns that year into a planning date and lists what to check when you reach it. Use that page for timing, and use this walk-through for the upkeep between visits.