My favorite things to wear are dresses and skirts. I have a somewhat important date coming up tomorrow and I was planning on wearing one of my dresses, but I unfortunately fell during a dance class and a dark black and blue mark on my knee, and a smaller one on my ankle.
If you're comfortable showing the bruises, wear a dress or skirt. If you're not comfortable, cover them. I've walked around with huge bruises before and no one ever looked at me like I was crazy for it. People get bruises, it's a fact of life.
Talking about your bruises will make conversation. If he asks first, it also shows he's concerned about you which means he likes you and notices things about you. Go for it. So don't say anything and let him ask first.
I'd wear it and I wouldn't care if a bruise was on my knee. I say go for it. If you love wearing skirts and dresses rather then jeans then by all means wear skirts and dresses. If you force yourself to wear something you don't feel comfortable in or don't like. Then you'd feel distracted from your date. Wear anything you like. Whether it shows your bruise or not! And its not like. People are gonna stare at your bruise. If you look good. I doubt that even your date will notice.
If you love skirts and dresses then try putting a little foundation on it to cover it up. That way you won't feel self conscious and he won't be staring at your bruises wondering what happened to you all night. Lol. Do what is going to make you feel happy, outgoing, and confident.
To be honest I wouldn't wear a dress, at least not the one in which the knee bruise is showing. The guy may not even think anything about it but I'd feel insecure, because if he does notice he may get a wrong impression about you. Maybe that's just me though.
Pshhhh, I say go for it... I doubt anyone will really be staring at your knees and your ankles the whole time anyway. :) I love dresses too, they are my favorite for the summer!