Sparkly: Swap something that you don’t want to do now with something new and closer to want you want.
Like not watching tv, watch a video online. Torahcafe, Jewish.tv, even a shiur on YouTube.
As for something like not wearing shorter skirts, someone once gave me the most amazing advice. She said every time I go shopping, to try to buy one thing. If I buy one thing, then I should also feel good about it. Changing what you wear takes a long time. Your clothes are an expression of you.
Before even buying that one piece, try on longer skirts just to see yourself in them. Maybe a longer dress. Something that still feels like you and something that feels the opposite of you. You may surprise yourself in what looks good on you.
Not talking to guys is challenging. Maybe limit what you talk about with guys. Talk about school and classes, but if they seem to be talking about that stuff as a way to get you to hang out (which seems like almost always), then find a reason to say that you have to go. You don’t need to explain. Just bounce.
What’s wrong with Jewish music?