[ol][li]Open Evolution, and go to Edit -> Preferences in the menu[/li][li]Delete your current account in the dialog that opens, and then click Add to start configuring a new account from scratch. Click Forward.[/li][li]Enter your full gmail address in the correct form, and click Forward.[/li][li]Make sure that ServerType is set to IMAP, Server to imap.gmail.com and Username to the first part of your gmail address (the text before the '@' ). Then set Use Secure Connection to SSL Encryption and Authentication Type to Password. Press Forward twice.[/li][li]Make sure ServerType is set to SMTP. Then set Server to smtp.gmail.com:465, click the checkbox Server requires authentication, and set Use Secure Connection to SSL Encryption. Under Authentication, set Type to Plain and Username to the first part of your gmail address (the text before the '@' ). Press Forward twice, and then Apply.[/li][/ol]
Note that contrary to the GMail instructions, you have to use the alternative SSL Encryption and not TLS Encryption for SMTP.
Hope this helps :)