I often have slight reflections in my lens when the sun (or another bright source of light) is directly in front of my camera. As a result of this effect I had to change the composition of my picture! What is the right way to avoid reflections when Sun is in front of the camera? Is there any way other than changing the composition?
In general a lens hood can help this, as can shading the lens with your hand (this if useful in the cases where the lens hood falls short of offering optimum flare protection, as is often the case with zooms, or full frame primes on APS-C). Shading only works when the lightsource is outside of the frame, however.
Of course the best way of avoiding flare is by not shooting into the sun (or any other lightsource). But for the times when this is not possible, removing any lens mounted filters may help. Also when upgrading look at reviews that tell you how badly a lens flares, as some are much worse than others! Finally try and use flare as an artistic element in the picture!
This might be obvious but: don't shoot towards the Sun, what's not so obvious is the angle on which your lens "is more sensible to capture the light to the lens flare" varies a lot. Usually wide angle lenses are very prone to this, because they have a protuberant front element and smaller lens hoods
Some lenses are more resistant to this effect than others. Optical construction plays a large part - how many individual lenses are there inside, how are they shaped, how are they coated.