amber

When passing through a lock, an amber light means “approach the lock under full control."

What you do is put your key in the knob and turn it. You should feel a slight resistance when you have turned it far enough. Then you would remove the key. You may have to turn it back to center with some lock sets. If you are not in the habit of locking a door this way, or keep forgetting which way to turn it, you should get into the habit of checking the knob to make sure it is locked.

A simpler way is often to lock the door using the toggle on the inside before closing it. Just make sure you have your keys with you before pulling the door. This is likely the most common way of getting locked out. There are also lock sets on doors which are self-locking.

To unlock, you would turn the key the other way, and you may have to go back to center to remove the key as above.

If the above is too complicated to understand, you will just have to practice on an actual lockset.

lock

Some people will swear by using a credit card to unlock bedroom doors from the outside, sometimes a small screwdriver that fits in the keyhole will jostle the door open, and other times the door just doesn't work that way and will not open without a key. Good luck.