mmm I'd say cologne definitely but you know it isn't necessary but there are some fragrances with pheromones in them to attract the opposite gender, I definitely liked styled hair but the hair on some guys looks perfectly fine without being styled. Wear fragrances in moderation though as some guys go overboard with it. I like long sleeved shirts on guys and collared ones I have no idea why but I know that's what I like. lol. And I like some guys in shorts others look best in pants because some tend to have chicken legs so,... haha,...but I really think guys look great when they dress formal,..
You shouldn't worry about what others want only what you want. If you want to impress a girl, throw on whatever you think looks nice, and some cologne that you think smells good. As for hair, do what you like best. Girls are attracted to different guys, some like 'em bald, with mohawks, curly hair, longhair, scruffy hair depends on the girl. You should never \change your likes for someone else's needs.