Setting up the RosterSMS calendar for any Android device is the same as: Calendar Setup: Android

Follow those instructions first.

If you are using Google Calendar App and the calendar does not appear, then follow the instructions below:

1. In the Google Calendar app, press the menu button to display the following options and scroll down to the bottom of the list:

2. At the bottom of the menu, click on the "Settings" option:

3. Click on the "Manage accounts" option:

4. Ensure that the RosterSMS calendar button is on, to enable the calendar display: