the chai is trying to move down one cog on the cassette so which way do i turn the adjuster on the gear shifter – anti clockwise or clockwise?

not sure what type of rear mech it is (XT deore) but the chain moves down the cassette (from large cog to small) when i slacken the gear cable if that makes any difference

thanks

http://www.parktool.com/repair/readhowto.asp?id=64