There are lots of effective freestyle techniques, and all of them have two things in common: breathing and body position.  Expelling air underwater to prepare for a breath, then a quick and minimal turn of the head to take in some air are hallmarks of great freestyle breathing technique.  Breathing technique is important, but as swimmers, we spend a lot of time not breathing.  Keeping good body position with the head down and torso in a straight line promotes efficient and fast swimming between breaths.