It all depends what you like about a person. You can use that as a basis for your criteria, such as do they have to be sporty or not? Do they have to be into the same type of music as you? Do you prefer a calm or sedentary person, or perhaps a more hedonistic, spontaneous person? Are you offended easily by certain types of jokes, remarks or sarcasm or are you an easy-going person who isn't offenede that easily? If you are easily offended you may want to go for someone who isn't likely to say such offensive things. Or if you are not easily offended, then you may want to go for someone similar so that you are not feeling you have to constantly watch what you say. I could go on, but at the end of the day, it is entirely up to you what your criteria is.