I just go back and fourth to my room to play troughout the day, maybe an hour at a time, and it usually just rounds out to about 6hrs. (on a good day :) )
Someimtes I practise scales (I just finnished doing that) or learn a song, or just improvise, or make up some cool chords and figure out what they're called, or even just listen to a guitar based song. Its all pretty spontanious, and its more fun that way I find, and practising should be fun, or else you'll start looking it at it as a chore, and thats the last thing you wanna do.