Conditions of light
Light is the single most important factor in photography, without it you wouldn’t get pictures, but there are different types of light to think about and as a general rule, early mornings tend to be cooler (blue) evenings tend to be warmer (red), mid-day is white (harsh) light, so for more interesting pictures use dawn or dusk, Sunny days, mid-afternoon are not very interesting, look for storms or diffused light (below) - or try other things, interesting colours/shadows etc. See below for more examples of different lighting conditions
This shot was taken in the evening, the hour before sunset - the Golden Hour (See application screenshots below)
This shot of the same hill and lake was taken the following morning - roughly an hour before sunrise - The Blue Hour
Back lighting - When the sun is still bright, finding interesting shadows, or back lighting the subject can make for interesting images.
Overcast - When there is heavy cloud cover the light is 'diffused', meaning it is largely even across all surfaces, so there is not too much contrast.
Storms, Black clouds bring their own drama to a subject, particularly if there is some sunlight on the subject.
A polarising filter reduces reflected light from entering the camera, and has an effect on blue skies, water refection, reflection from glass, and on greenery etc. A lot of sunglasses are polarised, by tilting your head you can see the effect on certain surfaces.
The best effect from a polariser is when the sun is at right angles to the subject.
In the images below, because it has darkened the sky, this means it evened the exposure on the land. I leave the filter on my camera unless I have a specific reason to take it off.
Without a polorising filter
With a polorising filter
There are many phone apps available to enable you to track the golden hour or the blue hour, and also position of the sun/moon and times of sun set or sunrise, some of these tools will even pinpoint the time of the visibility of the galactic centre of the milky for Astro-photography - Three of the apps I use are shown below:-
The links are for the android versions, they are also available from apple - and there are many other available apps to use.