Unable to play FM 2011 because steam is offline how do I change it to online?

I have not had time to play football manager recently but fancied to finally start playing the game but for some reason it didn't load up so I turned steam to offline still nothing then uninstalled steam and football manager thought I would try to do a fresh installation but now when I try to install the game it says steam needs to be online to update set to online but I don't see how I can change it now. Can anybody help me please. I have a macbook if that makes any difference.