This is one of the easiest termal changes and the depature areas(airside) are linked by a corridor... walk from the lounge towards gates 36 - 59 and instead of turning left to go down the passage to the gates follow the curve round to the right and you will be in a corridor which i think is actually marked to Terminal 2... you will arrive next to terminal 2 gates 2 - 10 or there abouts.
hope this make sense
have a look at the pdf termanal maps at
www.baa.com