1. Click on Safari and then on Preferences.
2. Select Privacy and then click Manage Website Data.
3. Select Remove All and then in the small popup, select Remove Now.
4. Click Safari in the menu at the top of the screen and click Preferences.
5. In the Preferences window, click the Advanced tab and make sure the checkbox next to "Show Develop menu in menu bar" is selected.
6. Select Develop in the menu bar on the top of the screen and click Empty Caches.