Clicking on a case opens it up in the right-hand panel. From here you can take actions on the case.

Assigning cases to yourself

In the upper left corner, you'll see the Assign me button. You can click Assign me to assign the case to yourself. To the left, you'll see the profile picture of the user the case is assigned to, which will look like a question mark if the case is unassigned.

Delegating cases to other assignees

Click on the drop-down menu icon next to the “Assign me” button. From the menu, select the assignee for the case. An email alert will be sent to the new assignee when a case is assigned.

Case Manager - How do I assign cases?