While assembling a key organizer is quite straight forward (and fun), it is worth of giving it some thought before you put all keys together, and it is for two reasons. First, when having more than 4 keys added, you want to ensure an easy access to all keys including those hidden in the middle so you can conveniently access any key whenever you need.
The second reason is at the same time one of the greatest benefits of having an organizer - you can hide sharp edges that your keys have and protect your legs or any other item you carry together with your keys in your pockets from being scratched. If you would like to learn more sorting keys and placing these in an optimal setup, consider visiting our special guide: How do I organize keys with a key holder?
As a general rule, the most common keys (typically those with a length of up to 6-7 cm) go inside. Any other keys that are longer or have a bulky form (like some chub or car keys), you can attach through any key ring. When you are done, you simply fold all of your keys before putting it back in your pocket. If you need to open a door, find the key and fold it out; afterwards just fold it back.