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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As you catch and pull through, lift your head and look forward and then immediately rotate to the side to breathe with the stroke. Drop your head back into the water as you do so. 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 drag and there's very little interruption to your stroke. 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 find that you veer off course all the time then working on your symmetry should be a priority for you. Something as simple as bilateral breathing can make a huge difference to your ability to swim straight in open water, saving you large chunks of time and energy.