You might be able to do a bit better; learn a simple and catchy system like the True Colors personality spectrum (a simplified adaptation of the Myers-Briggs), and work on understanding why it works. (Or if you like, why it "works".) While you might guess someone's 'color' incorrectly, if you understand why everyone identifies at least a little with every color, you can start to use general, positive statements to identify what people like about themselves. It should be a productive exercise in understanding the average person's self concept.