Hi, I was thinking of accompanying a friend to Penang and was wondering about the necessary preparations if there are any. I am on a triple entry visa which the first 60 day period does not end until Jan 14th. Is there anything I need to do before leaving so as not to disrupt my visa status?

...Also, I am a newbie at this, but I was told I can go to Sumoi for my visa extension... is that correct?

I am assuming that the application for the extension should be done early enough that I will still have time to go for a visa run, should they not grant it... I am presently in Koh Phangan.

Your stay will end if you leave Thailand and entry would be on the next visa allowed entry for a new 60 days. If you prefer you may be able to obtain a re-entry permit to keep your current stay alive but with a valid visa they might not want to issue. If they do you could return for the same permitted to stay date you currently have and extend normally if that is the plan (at Samui). But you may want to check the validity of your visa also as all entries must be made within that time. A re-entry permit would cost 1,000 baht and a trip to Samui to obtain (it can not be obtained at land exit points and have no reports of it being available at Samui Airport).

You could do you 30 day extension at the same time that you get the re-entry permit. That would save making another trip to immigration and might make it easier to get the re-entry permit which would then be valid for until your extension ends.