New Word documents are automatically created in Editor mode. This mode lets you immediately start creating and formatting your Word documents using the full range of OfficeSuite's editing features. To switch to Viewer mode, tap on the 
Viewer icon in the upper right.
While editing, you can tap on the 
Undo/Redo icon to retract the latest change you have made. Holding down on this icon will reveal the Redo option, where you can reapply document changes.