Instructions for enabling WordKeys after installation:
Go to settings, language & input, and check the box by WordKeys.
You will be prompted with a warning about the fact that the input method could collect personal information typed in. WordKeys does not collect any information, and it does not have permission to access the internet, so it would not be able to send your personal information anywhere either.
After enabling WordKeys, click on Default and select WordKeys.
If the version of Android on your device doesn't have the Default setting, after enabling WordKeys go into input mode in any app, such as text messaging. Do a "long press" in the input area, select "Input Method", and select WordKeys.