First, you'll have to go to app.signagent.com
When you arrive, click Register to create your new account
When you get to this page, you'll have to enter your email and choose a password.
Note that, rather than basing it on specific character criteria, you just have to avoid using words, names, common passwords, or keyboard patterns. Some examples that WON'T work are:
Some examples that WILL work are:
oh password my password
this whole court is out of order
I just can't wait to be king
I love SignAgent
A good general rule is to use 2 or more words that are easy to remember, but aren't the same.