[Jessica Boucher]

Actual lady here. There's a couple of things you want to think about:

1.) Ian has it right: dress up nicer than normal those first new days. People will excuse the over-dressing since you're new, and you can then ease into a pattern that works or find someone to get advice from.
2.) My goto is button down, dark slacks, and lower heels. That works for the majority of situations.
3.) Context is important: If you'll be visiting shop floors or anything that has a separate dress code for safety, try to work that in. My last job had a manufacturing floor so I only wore closed toed shoes and pants, but now I'm 100% office so I can wear skirts and such.
4.) Play it safe. This goes for accessories, perfume, hair, makeup, etc. Don't forget them, but don't go overboard.

Good luck! Let me know if you have anything specific you want to discuss.