How to pick ens name?

As a cryptocurrency enthusiast, I'm often faced with the task of selecting an Ethereum Name Service (ENS) name. Could you elaborate on the key considerations when picking an ENS name? Should I prioritize uniqueness, memorability, or relevance to my business or identity? Are there any specific formatting guidelines or character limitations I should be aware of? Additionally, how do I ensure that the name I choose is available and hasn't already been taken by another user? Finally, are there any security best practices I should follow to protect my chosen ENS name from malicious actors?