If you are just starting out in photography, I highly recommend you get a polarizing filter.  This filter comes in two forms: the circular and linear.  I recommend the circular because it is easier to use and carry because is screw in the lenses.  This filter reduces glare and increases to taste, because you can adjust, this type of filter.

In this case, I used the filter to cut some reflections in the water so that the rocks barely looks beneath the sea.

However you can do the opposite and make the water reflects the sky and clouds.Here I made ​​a small diagram to show the best moment where more reflections can be achieved and that is when your light source is 90 degrees from your subject.

Sorry I’m not that skilled at drawing and it was made in the iPhone.

The blue part is a lake and when the sun is at 90′ angle you can get a lot of reflections from the water, making it like a mirror for the sky.

Now go out and shoot!