well i always advise practice........but since it seems people need as detailed an explanation as possible here goes.
make sure the rack is frozen of course.
don't put "as much force as humanly possible" because odds are, you can't control the cue ball at that speed. try using 60-70 percent of the "humanly force"
make sure you hit the one ball square. a tip below center usually does the trick, but you'll have to experiment as some people tend to come upwards or downwards during the break........but usually a tip below center will stop the cue ball or back it up a few inches.
if you need somewhere to aim, blackjack advocates finding the point where the 1 ball actually touches the cloth, its a small point but makes a good target. he has more detailed lessons on breaking.
if you're still not making any balls after doing this, change the position on the table you are breaking from.
after doing all this there is no reason that you won't be making balls.
thanks
VAP