This is a tough question for many young ladies to answer these days. You are constantly being bombarded with teens and young women who aren't wearing much. I give you lots of credit for recognizing that you might fall into that category and are willing to do something about it.
I found this great website at address this issue. I think you will find it helpful. There are additional links at the end as well.
Marebear - the member who asked this question - selected this as the best answer posted by another Education.com member.
from a fellow member
I would first like to say that I'm very impressed by your self-realization to dress modestly at your age! Many teens don't seem to care about how much skin they're showing. I fell into that category when I was in High School and looking back on it, I wish I covered up a little bit more... So kudos to you!
Completely changing your wardrobe sounds like a fun process. You have an opportunity to take charge of what clothes you want in your closet and developing your personal style. You might be able to salvage some of your favorites by wearing layers (also perfect for staying warm). Camisoles are great to wear under a blouse with a plunging neckline. If you're wearing a dress/skirt that's a little on the short side, always make sure to wear shorts underneath or pair them with some cute leggings.
Another fun idea is to "google" some of your favorite celebrities to get some ideas (Britney Spears & Taylor Momsen would not be the best for modest style advice). I like Selena Gomez's and Taylor Swift's styles- they're fun, age appropriate and I can't recall them wearing anything too revealing.
Below are some articles that you might find useful.
I am raising 3 girls, yet it feels like it was just yesterday that I was your age. So, I am going to tell you like I tell my 15 year old sophmore. There is something to a beautiful girl who knows how to leave something to the imagination of the scoundrel who's looking. lol...Cover up your breast,no cleavage at your age. If you have to show bellybutton (I prefer you didn't) at least be wearing a pear of pants that aren't too tight or too low around the hips. Skirts should be around the knee area. No mini-skirts and high heels. Knee skirts or dresses with a modest heel, ok. No heavy make up or perfume. Makeup lightly applied with a light gloss. Note sweetie: You don't have to look trashy to feel and look sexy. Feel your femininity from the inside out and you will exude confidence which is very appealing. I hope this helps. ;)
Well I am very much impressed with your thought of dressing modestly instead of showing skin. However you will feel peculiar in crowd as women are now exposing in a big deal. Making complete change in a wardrobe with modest dress sounds exciting. You can make this possible by the help of Leelach online shop. They have wide range of modest dresses including the great choice for plus size women and expectant mothers too. Bring a list of what clothes you want in your closet and full your wardrobe with the beautiful collection.