Nothing wrong with whipping those mini skirts out just make sure that when you bend down to pick something up you don't see anything "inappropriate". Although inappropriate is greatly debatable these days :p
You can not dress slutty. You can only act slutty..
If you are a slut already and then wearing things that show a lot of skin etc..then you are a slut but if you are not a slut and showing skin...then you are just showing skin. That is all. She sounds jealous..
I got 4 uppies for this on another question. So I suggest you follow my answer
Not if you wear a T-shirt on top. The tip is BALANCE, showing your legs means you shouldn't show too much skin on top (i.e. don't show too much boobs). But any outfit can be classy and sexy if you know how to style and mix your outfits. And it's how you carry yourself, as long as you don't act like a "slut", you won't be percieved as one. Besides, it's summer, wear your miniskirt, girl!