You can update everything in the Hub! After logging in, click on your name in the upper right hand corner. Select "Profile". You'll be taken to a page where you can update your personal information, as well as the category your occupation best fits into. 

If you are willing to be added to our list of substitutes, simply click the box next to "Substitute". 

Once you're done making changes, hit "Save" and your information will be updated!