This guide tells you how to quickly and easily get started with Exchange Online using a 10 user free trial which can easily be converted to a paid subscription later ($6 per user per month, minimum 1 user)

This is how you do it (steps may vary a little bit depending on what country you are from)

    1. Go to Office365.com
    2. Click “Get the trial”. This will give you a fully functional free 10 user trial for 30 days.
      So this means one month free and you can test everything before you start paying. When the trial period is up, it is easy to turn it into a paid subscription. No rebate coupon or voucher code needed.
    3. Select the option for “Professionals and Small businesses”, this is the “P1” plan. For some countries this may already be preselected.
      (If you are a larger company select the “Midsize businesses and enterprises”, plan “E3” but note that pricing, features etc is different from what is covered here)
    4. Fill out the information about yourself to create a Microsoft Online Services ID.
      You will have to select an onmicrosoft.com domain name, e.g. mycompany.onmicrosoft.com. Don’t worry, you will be able to add your real domain name (or multiple domain names) later
    5. You should see a page telling you that Exchange Online, Lync Online and Sharepoint Online is being set up and that it will take a few minutes. Wait for them to finish.
    6. Add your own Domain. a) Click Admin in the top navigation. From the Admin page on the left column navigation b) Click Management-Domains, then c) Click Add a Domain. d) Enter your domain name and click the Check Domain button. After domain information is shown e) click Next and you will be taken to a page with instructions how to add a TXT record to your DNS for verifying your domain.
    7. Add users. a) Click Admin in the top navigation. From the Admin page on the left column navigation b) Click Management-Users, then c) Click New + User and follow the instructions.
      If you wish, you can make the admin user that was created when you signed up just an admin account without a paid license. To do this edit the user and uncheck “Microsoft Office 365 Plan P1” under License.
    8. Add me as your partner – optional. Thanks! a) Click Admin in the top navigation. From the Admin page on the left column navigation b) click Subscriptions-Manage, then c) click your subscription, Microsoft Office 365 Trial (Plan P1). On the far right you will see d) Partner Information, click Add and e) in the box shown enter 1912364 as partner id to use my company XS Tech as partner and click Ok (or if you prefer to use another partner enter their partner id) Thanks.

Done!

Background
Microsofts cloud offering Office 365 (formerly BPOS) includes among other things Exchange Online, Microsofts hosted email offering.
Exchange Online can be accessed from a browser (Outlook Web App), Outlook (Windows), Entourage or Outlook for Mac or any mobile software supporting ActiveSync, e.g. Android, iPhone, iPad, Windows Phone etc.
I find Exchange Online well priced at just below 50 SEK (US$ 6) per month for a 25GB mailbox with Sharepoint, Office Web Apps and Lync also included. It is half the price compared to my current Hosted Exchange provider and with over 10 times the storage. Extra plus for me is also that my Hosted Exchange provider is running Exchange 2007 while Office365 is on Exchange 2010. New with the change from BPOS to Office365 is also that you can now signup for only one single user instead of the previous minimum of three.

Browsers
I recommend using Internet Explorer or Firefox with Office 365, Exchange Online and other Office Web Apps. Chrome (currently in release 14) is working most of the time but not always.

Disclosure: My company is a Microsoft partner.