Step 1: Go to www.playstation.com, you should automaticly be redirected to the site in your language
Step 2: Either create an account or login to your existing one
Step 3: Click "my account" and go to My portable ID
Step 4: Once you're done creating one, copy the given html code
Step 5: Go to the K!PTeam forums, and go to account settings by clicking your name on the top right. Click "Edit Your Signature" and paste the HTML code you copied earlier. Don't forget to check the "Signature is in HTML Format" box.