In order to make sure that the time shown for events on the calendar will be local to you, you have to set your timezone correctly in the users settings.
How to do so?
1) Access the user menu in the upper right corner (click on the arrow next to your name) and choose "User settings"
2) Select the tab "Shivtr Account" (the second one from the left) and select your timezone.
Don't forget to update the settings!
3) You can check that your settings are correct by going on the events page :