Anyone with a Google account can use the free Google Calendar. You can share your calendar with friends and sync it across devices like a mobile phone or tablet computer. Because the calendar exists on Google's servers, you can access it from any computer with an Internet connection.
You can open the Google Calendar directly by going to https://calendar.google.com in a web browser.
Or you can open Gmail and choosing Calendar from the Google Apps menu at the top right of the browser window.
Click on any blank space on the calendar to add an event or appointment. Enter the information, like the name of the activity and click Create. If you prefer, click Edit Event, after which you can fill out a lot of more details.
Here, you can fine-tune the date and time, add details, and invite others to your meeting. The Event color section lets you choose what the event looks like on the calendar. When you're done, click Save.
To associate an activity with an entire day (rather than a time slot), click in the box at the top of a day, above the time slots and repeat the process from step 3.
By default, this all-day event will not mark your day as busy, so others will think they can invite you to other events. If you'd rather mark the day as busy, click Edit Event and choose Busy from the From me as option at the bottom and save your changes.
If you want to invite other people to an event, open the event details and add guests using the Guests field on the right side of the page. Enter their email addresses.
When you're done, click "Save" and you'll get the option to send invitations to the people you selected.
You can view your calendar by day, week month, and other options. These are controlled via the settings above the calendar at the top of the page. Note that you can move forward and backwards in time using the arrows, and zoom right back to the current day by choosing Today. Looking for a specific meeting or event? You can search with the search box at the top of the page.
You can make your calendar available to others as well. Click the arrow next to the name of your calendar in the left-hand menu and click Share this Calendar. You can choose to allow public access or enter the email addresses of people you want to view your calendar. If entering individuals, you can grant different levels of access like whether they can make changes and see the details of all events as opposed to seeing only whether you are free or busy.