Most Helpful Guy
Most guys are going to say they don't like makeup, but most guys are ignorant on the subject (myself very much included). When we say we don't like makeup, we don't like noticeable makeup. A lot of girls wear a minor amount of makeup, and I think guys would think they were wearing makeup. Even if it's just a little eye makeup to look "awake" and "refreshed" - I think guys would prefer that but wouldn't necessarily notice that makeup was on.
That's for day to day. For nighttime, I think smoky eyes are very sexy. I even think some daring colors (blues, purples, reds, etc) can look very sexy.
It's literally the difference between night and day, I guess.