Document cleanup is for batch deskewing and rotating document pages. It can be found on the right click menu when selecting a document or group of documents.
Running any of these operations across a range of documents will perform it on every page of the selected documents so make sure that's what you want to do before starting.
To rotate individual pages in the Viewer pane, use the Rotate Clockwise or Rotate Counter Clockwise buttons on the toolbar, or click the hotkeys - "[" for Rotate Clockwise and "]" for Rotate Clockwise. These hotkeys also work in OnCue LIVE.
To manually deskew individual pages in the Viewer Pane, use the nudge buttons on the toolbar to rotate in small increments, you can also use the hotkeys of Shift+[ and Shift+] which also work in OnCue LIVE.