If you're an admin of the organization, you have the ability to turn setup mode on and off.
Step 1: Go to your Admin menu and select "Organization Settings".
Step 2: Select the "Constitution" tab.
Step 3: Look for "Advanced" at the very bottom of the page and turn setup mode off /on from here.
For introductory information: What is Setup Mode?
For further information on how setup mode works: How do I use Setup Mode?