After your application for membership is approved on this site, you will be invited to the Guild chat tab in-game. Here are the steps to take before accepting the invitation:
Step 1: Go to Setup (F9 key), Misc tab (3rd from right), scroll down and check the box that says "Enable guild bot support and disable native guild support", then click Apply.
Step 2: Go to Setup (F9 key), Players tab. The 9th line down is Badges. Choose one of the "show at ..." options, then click Apply. (I prefer the badge to "show at bottom", but you can choose your own preference.)
Once you accept the invitation, the Guild chat tab will become visible. You should see only 1 guild tab, with an upper case "G". If you have 2 guild tabs, delete the one with the lower case "g".
Also, fellow guild members' names will appear in color and the CRC guild badge will be visible to you. You may need to relog to see these changes.
(The CRC guild badge was created by Quartermaster Micksha and is a representation of a treasure chest with a shiny golden coin rising out of it. On one side the coin has the printed letters "CRC", and on the other it shows the Manaworld symbol with crossed swords below it. The badge is visible only to members of CRC.)