If you already have a Google account, for example you are a user of GMail, then you are able to access the calendar option straight away.
For those who don't have an account then it takes a couple of steps to create one and you will be able to build a calendar, but also have access to Google Docs and many other tools.
Before I go any further there is one issue with a Google Calendar that I've not been able to beat and that is you can only display the current month on a web page.
If you are keen to display a 12 month span then at the moment I don't think it is possible, but if that's not a problem here's how to get your first calendar up and running.
When you first log in you will have the option to create a new calendar and so give it a name, a short description if required and you will notice that by default your calendar is only viewable by yourself - which is fine for now.
From here I'd just start entering a few phantom events to get an idea of how quickly and easy it is to use the service, so you can add individual events on a certain date or fill a full week, ten days, two weeks, any length of time really.
And as you play around with this you will begin to see what you can do with the calendar, so for example, if you take a booking for the first week of April then you fill these days with a note saying such.
But for the weeks either side you can highlight that these are free and even include pricing details so that people can compare weeks.
As you get more confident with the tools built into the calendar, the help pages are very comprehensive, you could begin to highlight events that are on in the local area, giving potential customers a bit of an insight into what's on during their stay.
If you are happy with your Google Calendar the next step is to make it available for search engine spiders to crawl, as well as visitors to your website to view.
From within the settings for your calendar you can Share this Calendar, which means your events, and free dates, are publicly available for people to find via search engines.
Then if you head to Calendar Details and scroll down the page you can embed your calendar on a web page with a bit of copy and paste - but first you might want to customise the colour, size and tweak a few other options.
On this page you can decide to display things such as navigation buttons and tabs, if you are keen to offer up a lightweight calendar I'd just display the Date and Print icon.
It is on this page that you can tweak the width of the calendar to ensure it sits snugly within your website.
And it is here where the issue of only being able to display the current month has left me stumped, because people will have to use the date option in the top left hand corner to click through to when they want to stay.
Clearly not the biggest problem and you could easily tell people that they can browse through to the month of their choice with a short explanatory line just above the calendar.
Like the contact form I wrote about earlier your calendar is accessible from anywhere in the world should you need to edit any details, and as both services are run through Google you can take a booking and update the calendar in a couple of clicks.
Below is a quick example calendar with the Date and Print icons on display, and as ever if you've a question, or any other tips on using a Google Calendar, please feel free to leave a comment.