You can find the full list of instructions, for setting up your email in MS Outlook, at:
https://support.google.com/mail/bin/static.py?hl=en&ts=1668960&page=ts.cs

You'll be asked a series of questions, in the blue boxes... here's the answers to choose:

  1. I want to enable IMAP. (That'll keep messages you read in Outlook read in the Webmail, and visa-versa).
  2. Outlook / Windows Mail
  3. Ok, confirm my settings

 

For both your "Account Name/User Name" & your "Email address" use your _full_ email address.
e.g. myname@example.com

;)