If it's one thing we all love (or mostly love), is making a new, unique species. What of yours? Do you keep your species humanoid, resembling Earth creatures, or is it completely new? Futuristic, modern, etc? Society? Conflicts, interesting facts?
Personally, I try to make my species as un-human as possible- I like to test what it would be like to live as a snake-like sentient being with four arms, and hollow horns for echolocation. It's interesting to imagine just how different they can be.