The correct technique is to keep your head much lower, just raising it enough to lift your eyes above the surface of the water:
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When do you breathe? Immediately afterwards and to the side. It looks like this:
As you catch the water and pull through with your lead arm, lift your head and look forward. Then immediately rotate to the side to breathe with the stroke, dropping your head back into the water as you rotate. The whole thing is one smooth fluid action and it takes less than a second to complete.
Practise this technique in the pool and get used to timing your head movement. It's normal for it to feel quite mechanical and awkward at first so allow yourself around six sessions and it will start to feel much more natural.
Turn A Fuzzy Picture Into A Clear One
The great thing about this technique is that it creates less downward pressure on the legs and so less drag, there's also very little interruption to your stroke rhythm. The downside is that you don't have very long looking forward, so hold the image of what you saw in your mind and analyse it afterwards. With any sighting technique you won't always get a clear view of what's ahead but that's OK - don't panic! Perform a couple more strokes and sight again and you'll gradually turn a fuzzy picture into a clear one in your mind.
How Often Should You Sight?
Anywhere between every 3 and 12 strokes depending on the conditions and also on the symmetry of your stroke. If you have confidence that you swim straight then you can afford to look forwards less frequently, avoiding the extra effort of lifting your head and the downward pressure on your legs that results.
If you find you veer off course all the time then something as simple as bilateral breathing during your training can significantly improve your stroke symmetry, helping you to swim straighter and faster in open water as a result.