1. If you want to become ladylike, you should become familiar with one word, namely "elegance". Elegance is elusive and depends on the person in question but you can get an idea if you watch Breakfast at Tiffany's or read Jackie O's biography. They are well known as persons who define elegance and that is what being a lady is all about. Lead men on, marry rich guys, buy diamonds, be born before 1950.
2. Maintain your cleanliness. This is important to being a lady. You can't be elegant if you haven't bathed in 2 days or washed your hair in a week. Wear deodorant, bathe often, wash your hair, wear perfume, and the whole nine yards.
3. Be well mannered. Manners are a necessity to being ladylike. Read up on books that teach etiquette and always be nice to everyone, but at the same time, don't be a doormat. Saying "Welcome to Our Home" all of the time is boring and your texture would be unpleasant.
4. Dress appropriately. Your clothes can tell a lot about you. That doesn't mean wear skirts that you trip over all the time, but it means keep it clean. And by clean I mean both (1) spotlessly well washed and (2) not sexually suggestive. Not a lot of people will want to see every little detail when it comes to you. Who do you think you are, Jackie Onassis? You never married JFK. Also, sit with your legs crossed at the ankle so no one sees more than is necessary.