I think almost every home has a drawer with random keys and locks in it. For many, the locks may be without keys or combinations and the keys are to known and unknown locks.
The first step in organising keys and locks is to gather them all in one place. I suggest using a small, lidded bin, such as a shoebox. Place all the locks and keys in the bin. You may have lockable cabinets or doors that require keys. Of course, you can’t put furniture into the shoebox but you can make a list of furniture that require keys and put the list in the shoebox, too.
Purchase a few key tags and write what the key is for on the key tag right away and attach the tag to the key. If padlocks are not in use, put the hasp through the key ring with the keys and lock it. This will keep the correct keys with the correct lock. Just remove one of the keys from the keyring to unlock the lock.
If you have combination locks, write down the combination on a key tag with a description of the combination lock and/or its serial number. If the locks are simple, such as suitcase locks with only 3 or 4 numbers, you may be able to fiddle with it enough to determine the combination. Some rotary dial combination locks have serial numbers and you can get the combination by contacting the manufacturer. If the combination lock is not in use, put the hasp through the key tag on which you wrote the combination. You’ll never worry about trying to remember the combination.
Store keys that are used frequently close to where they are used. For example, you might keep a key to your garden shed on a hook, just inside the back door. Extra house keys should be labelled and stored in a key cabinet.
Keep mismatched keys and locks in the labeled shoebox for a few months just in case their mates turn up somewhere else. It is also helpful to ask family members and coworkers if they have seen any keys or locks “hiding” anywhere. You may find someone else is in possession of the little key you were looking for. Ask them, too, if one of the keys you can’t identify may be a spare key to their home you never labeled. If you’ve determined that the keys and locks are never going to find their mates, feel free to dispose of them.
Remember, also, to carry only the keys you need with you. Separate the keys you carry with you into groups such as home, car, office, or cottage. Put each set on a different ring. Clip the key groups you need together with a carabineer when you leave the house to reduce the clutter in purses and pockets.