In Jason's case- you write- Special:AdminDashboard after his wiki link.
On any wiki- just add : Special:AdminDashboard after the link.
Then if you press enter and have access to the Admin Dashboard- this will show up.However if you do not have rights- like me currently on Jason's wiki- this will show up instead. Next, if you want to PROMOTE someone then go to the USER RIGHTS BUTTON. Then type in the username that you want to promote/block. Look at the following picture. Then hit ENTER. There you will see a list of a buncj of rights. Select B-Crat or all boxes for the desired position of that person. As I have done on my wiki- I selected all positions for myself in the following picture. Then just SAVE USER GROUPS, and you're finished. All that is left is to congratulate that User.