Changing your email address is a simple process. However, if you don't do it in the proper sequence, it can affect your permissions.

When you first sign in, you will either see a list of all the groups you are a member of, or if you are only in one group, you will be taken straight into your account.

If you are only in one group:

Click the PROFILE tab.

Change your email address, then click the Save button.

If you are a member of multiple groups: 

Remain on the screen that shows all of your groups. Do not sign in to any of them; instead, click the Update My Information link that appears in the "My Account" area to the left.

At this screen, simply change your email address and click Save.