That's why the 'opposite' rule generally works for, well, everything. I think it was Poliquin that first mentioned this, but who knows. Anyway,
Do the opposite from 'everyone else', and you'll do better than them. Examples,
Most people eat a diet low in protein, fat, and high in carbs. So, increase your protein, fat, and lower your carbs. Drill it down some more - Most people eat a diet high in Trans fats, but low in the healthy fats (saturated, monounsaturated, polyunsaturated), therefore, get your fat from the healthy kind, and limit trans fats. (Actually just avoid transfats all together, but 'limiting' them makes the whole opposites thing work better).
Most people get most of their fluid from calories containing drinks. So, drink water, or green tea.
Most people do long duration, low intensity cardio to 'lose fat'. Therefore, do stuff that is short in time, and high in intensity.
Most people run to get fit. So, get fit to run (if you want to run at all, that is).
Most use primarily machines (in commercial gyms), so, you should use primarily free weights.
Most do excessive amounts of isolation exercises, so, you should do a limited amount of them.
Most people avoid squats and deadlifts, so, learn to love squats and deadlifts...
Most people eat 2-3 meals per day. So, eat 5-6 (or more) meals per day.
It could go on forever...
Most people chat for ages, read magazines, talk/text on their phone whilst in the gym. Therefore, just shut up and lift, and leave the phone in the locker.
Most people do 3 x 8. So, do 8 x 3.
The worlds ignorance can actually come in handy. If you're in doubt, just think, "does everyone else do this", if the answer is "yes", then it's probably not a good idea...