Too many websites give long winded explanations of creating SSH keys for a password-less login, following all of the useless extra commands can be tedious but it's actually really simple.

In the end it boils down to;

Create ssh keys, if you've done this don't do it again

ssh-keygen

Copy to server you want to login to

ssh-copy-id [email protected]

Don't forget to check your permissions!

Permissions of .ssh should be 700
Permissions of .ssh/authorized_keys should be 0600