Sizing frames
Make sure the round frame is still selected. When the frame handles around the frame are visible, the frame is selected.
From the Frame menu, select Properties. The Frame Properties dialog box appears.
Click on the Size and Position tab.
In the Size and Position group box, in the Width spin box, type 15.
In the Height spin box, type 15.
Click on the Close button in the top right-hand corner of the dialog box.