You are able to prioritize your calendar items by applying a High, Medium, or Low tag to your tasks and events. This will help you keep track of to-do items that are most important and require immediate action. These tags can be customized by Admins on your account from within Account Settings. You can add or edit these tags to give them new names that fit your business needs and even color-code them. 

When creating a new calendar item you will have the option to apply a priority tag. You can make a "default" tag by placing it at the top of your priorities list. When you apply a priority tag the name and color of the tag will show next to the name of your task on the Agenda and Calendar tabs making it easy to differentiate from other to-do items.