Open iTunes and check to make sure that you have the most recent version. Do this by clicking on "Help" and then clicking on "Check for Updates."
Use the cable that came with your iPhone to connect it directly to your computer. This will automatically launch iTunes. Select "iPhone" from the iTunes source list. Click on the "Info" tab in iTunes.
Click on the "Sync Outlook calendars" option. Click on "Apply" in the lower-right corner of your screen. Your computer will now sync with your iPhone based on your settings.