Google these words, the slang comes up on at least for links.

"slang in the 1930's"

The short answer to this is: DO YOUR RESEARCH.

The easiest way to do this is to read fifty novels written in the 1930's.

This is why teachers chant "Write what you know." To set a story in a time and place you didn't live through requires a lot of research. (Watching movies set then is not research and a poor idea, IMO. How do you know they did good research?) It took me a lot longer to research trains between New York and Chicago in 1938 through 1946 than it did to write the novella set there.

I recommend you seek photographs of the period set where your story will be, especially people about the right age, income, and social status for your characters. Pay attention to the setting as well; what businesses, street conditions, modes of transportation are visible?

Hit the library--no, not the internet, the real library--for magazines and newspapers of the era. What products are being advertised? What recipes are being published? What events are taking place that your character will care about? What impacts their daily lives?

Last, since you're at the library anyway, borrow books written in the 1930s. (Not written later and set then.) This is the surest way to know how real people talked--and more important, thought. It never works if you apply modern attitudes to people of the past.

I spent the 1930s in the New Guinea Highlands. I'd be happy to assist you with some tips on how people spoke and how they dressed. Would that information be relevant to your story? I'm wondering because you failed to stipulate WHERE your story takes place.

If you were writing a story set in 2019, it would be rather silly to insert the turns of phrase used in Australia or New Zealand if your character was supposed to be English or Canadian.

I've got a wild idea: How about you go read some goddamn books from the 1930s to see how the author went about crafting the dialogue?

If you don't know anything about the time period, why set your story in that era?

Are you doing it in the real 1930s or the movie 1930s like Bell's in The Batfry ep 211 http://thebatfry.libsyn.com/bells-in-the-batfry-ep...

My guess is Pictures on Archive dot org could be helpful

https://archive.org/search.php?query=1935

Do research on life in the 1930's then write your book.

Set WHERE in the 1930s? The world is a big place. A single country can have hundreds of cities in it, with people using different slang and local dialect.

Your young woman would dress according to her social class, her job (if any) and her age.

There is NO 'one answer fits all' for a question like this.

Why don't you go and READ a dozen novels set in the time span and location that you have in mind?

Do your homework. Research on how people lived in the 1930s and start from there. Check out a historical museum, I'm sure they have 1930s women clothes there.

Watch movie to get inspired