I have chosen to use Pinterest as the main site of reference images. I am familiar with it and I think it will provide a good base for gathering general imagery and idea. I am also practicing with Pure Ref as it is handy for keeping images together in one image file, as opposed to in a folder.

https://www.pinterest.co.uk/jazzy_121/design-a-world-settings/

https://www.pinterest.co.uk/jazzy_121/design-a-world-characters/