|Most people can get in the water and make the
swim appropriate movements with arms and legs for a short time, but keeping
it going for good distance is another story. Mastering the freestyle breathing
pattern is a challenge. You can't swim nonstop until you get comfortable
with breathing often enough to sustain your aerobic effort level.
The easiest pattern to master is to take a breath every second stroke. This means all of your breathing is on either the right or left side. The moment to breathe is when your pulling arm is halfway back, under your chest. If you're pulling with the left arm you should be breathing to the right side and vice-versa breathing to the left. The first year I swam almost all of my breathing was to the right; to the left I felt unbalanced and had no flow to the movement. Most new swimmers experience this.
Also, you should hold the air in your lungs until the moment just before your mouth breaks the surface. If you blow air out the whole time your face is in the water you may feel the need to inhale before you actually can. You'll also lose buoyancy. So for most of your stroke you're holding the air, then exhale-inhale just before and just after your mouth is above the waterline.
The natural tendency for new swimmers is to hold their head and upper body too high in the water. Our bodies have only so much float, so if your head and chest are high, your hips and legs will drop, slowing you down. Proper head position when you're not breathing is head facing down towards bottom of pool with just a sliver of your head above waterline, chin down, eyes looking mostly down toward bottom of pool. This is the correct position as your hand/arm is entering the water out front and during most of the stroke. If the water hits at forehead level your head is too high. The exception of course is sight breathing, more about that in another article.
You should not lift your head to breathe; in fact your head shouldn't move much at all as you swim. This is where body roll becomes crucial. As your hand/arm is pulling back at chest level you should be rolling your body so your chest faces the side of the pool, not the bottom. At this point of the stroke the shoulder of the pulling arm is going towards the bottom of the pool and the recovery arm's shoulder is out of the water.
As you take in air your head should stay low as the waterline essentially 'splits' your face with the corner of your mouth at water level. I can remember my first coach telling me: "Keep your ear in the water!"
You can get a feel for being on your side by just kicking with no pull. Kick with your arms at your side while rolling from face down, to facing the side of the pool, back to face down. It's easiest not to breathe with this drill, just stand up after a few seconds of kicking in the shallow end of pool.
Once you feel smooth breathing on your favored side, bi-lateral breathing is the next step. This is when you breathe every third stroke alternating sides. Bi-lateral breathing helps even-out your stroke, making it more symmetrical and efficient. If you need more oxygen than you can take-in every third stroke, breathe every second stroke and switch sides often.
Another common flaw for new swimmers is kicking from the knee with a motion similar to pedaling. A good kick is from the hips with only slight flexion at the knees. Good ankle flexibility helps your kick as you must be able to point your toes to create some thrust with the beating motion. Swimming with fins can help stretch out the tendons over the front of your ankle so toes can point, but don't train with them all the time though, as you'll have to leave them behind on race day!
One last technique issue to work on from the beginning is streamlining. Your body should feel long and all your motion is driving you forward, not laterally. Consider what happens with your hand out the window of a car at highway speeds in different positions. Just like this water offers a huge amount of resistance, so you pay dearly for any shapes or motions that make you 'bigger' in the water, causing extra drag. Practice streamlining as you push off the wall each time. Put your hands together out front, extend your arms from the shoulder and squeeze your head between them. Kick a couple beats, then begin pulling with arms again...