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Select My Apps in the top menu
Scroll across until you see Event Categories
You arrive on the Manage Event Categories page
Press the Edit button next to the event category you want to add additional states to
You arrive on the Edit Event Category page
Scroll down until you see the Add Guest Statuses box
Select the Guest Statuses you want to use on the event category
Drag the Guest Statuses up and down to arrange them in the order you want guests to be processed through them
Once done, press Save
You arrive back on the Manage Event Categories page