What about trying to take inspiration from day to day things, like a lamp? I look at my lamp (it's a free standing one with five maneuverable extensions coming out that each hold a lightbulb, and one bulb is green) and it reminds me of aliens because of its several limbs and then the other night when my nightlight went out (I'm not scared of the dark, I swear! lol) I adjusted the bulbs so only the green one would turn on and so I turned green, hence, another alien reference. From there I guess you would have to decide on culture and economy and the reason for the alien to be on earth or wherever, but those are easier once you know what genre you want the story to be which could be determined by your mood at that moment. This is what I do for inspiration, and not just from objects, but from conversations, inside jokes, etc.
