I wouldn’t reply, but I deal with teens so I will.
First remember you’re doing something you have a feeling for, and something that is a fundamental of the beautiful part of yiddishkiet. so you dont have to be worried if you’ll have the right approach, just go with the issue, and since you have valuable and credible merchandise (yahadus) to sell, it will carry. Of course being tznius goes part and parcel with talking in a courteous and respectful manner.
Its people like you who give us a good name, and personify and manifest all that is good.
The first approach would be to put forth why you feel so, but in a personal sense.
Example; “mom, I feel so weird going out exposed. It just feels embarrassing”. Also “I hate when people look at my legs, or stare at me. its sooo creepy’.
(If true- Use reverse teen; say all my friends are wearning this.)
Or -(on a different day, otherwise you will freak her out) mom, doesnt it feel so dignified when im – or you- dressed properly? and also I know when someone talks to me, he is treating me like a person.
Or “why do people go out dressed short and then tug it down all the time, if they’re uncomfortable why do they dress like that? Are people really so enslaved to fashion like that?”
Are you in an atmosphere where you mix with boys? if yes tell mom (and dad – you have no idea how supportive dads can be.)you want to keep away the psycho-s.
Psst; little secret; dads are so easy, an occasional smile, a short DMC, and no “deliberate in your face”, he is sooo owned. Like butter under a hot knife.
I hope this helps.
Lastly; keep searching- always. ENjoy the journey, being frum promotes happiness and is not an antithesis.
edited