i was told this in my 'events':

"Thank you for supporting Subeta by logging in during the last month. We appreciate your patience and understanding as we worked through our server issues, and we hope to continue improving the site with you! We've given you a week of free gold account as a token of our appreciation"

- I'm not sure what's not to understand? Subeta has been going through some problems lately, and everyone that logged in the last month got a week of free GA time to make up for it.

what do i do with it?

You don't need to do anything with it, per se; it's already been automatically activated. There is a stickied thread in this forum with all the common Gold Account questions, answers, and benefits if you're not familiar with them. ^_^