From the dashboard, choose a plan. Click the files tab to get to the file browser. Navigate to the file or folder you want to move, then click the clipboard icon beside it to add it to your clipboard. Next, navigate to the folder where you want to move the file or folder, and click the move files here link on the right under Clipboard items.
Note: Any items on the clipboard at the time will be moved, so before you clipboard an item, make sure you empty the clipboard by clicking the link on the right under Clipboard items.