You must remember that one of the key techniques to building muscle is varying it up. People that do the same workout routine for years start to lose their gains so make sure you're changing it every so often. Maybe you could train every muscle group once a week on a two week timetable where week#1 is heavy weight low reps and week#2 is light weight high reps.

Also, supersets work very well, if you're doing an arm workout for example, doing bicep curls followed by tricep push downs without any rest can be beneficial, it gets the blood and nutrients flowing as well as stimulating your CNS even more.

Heavy compound lifts are also needed to build muscle. You might associate things like deadlifts and squats with strength building but they actually stimulate your CNS so that you get maximum growth hormone produced and maximum recovery.

I hope this has helped a little bit,
Cam