Once you have created an account, you may either decide to join a public or private competition.
If you cannot find the competition you joined, try checking both the Live & Inactive competition tabs within the left sidemenu.
Joining a public competition
On the home page, click the side menu tab on the left Find a Public Competition. From here you may view a list of public competitions currently active on the site.
Joining a private competition
While on the home page, ensure that either Live Competitions or Inactive Competitions is selected within the left sidemenu. Click on the green button at the top of the sidemenu that is labeled Join a Private Competition. From here, enter the competition ID and competition password provided to you by the CTF manager.