A sketch without neat lineart, coloured, and with minimal shading
A chibi of one of your characters!
Humans, anthros and animals are all fine, but I have least experience with animals
A fully coloured and shaded drawing from shoulders up of your character
A fullbody drawing of one of your characters, human or otherwise! With a simple background of your choice. Anything with a hugely detailed landscape-y background would fit into the "Scene/Landscape" category
A full colour image of a landscape with or without characters
Also includes scenes of characters interacting (action shots, that sort of thing). Sorry if that's a bit vague, please feel free to note me if you're unsure