nervous for internship

Hi guys, couple months ago I asked for advice about an interview for an internship, im happy to announce that the interview went well and in two weeks I will start as a geology intern at a small consulting firm here in California. Im really excited but also very anxious as this will be my first ever time working in this environment. I was told it will be 70% in the field and 30% in the office which is fine. Im kinda nervous about the smaller things like what would be appropriate to wear? What do I bring with me on the first day? Any insight would be very appreciated haha. I don't really like to dress feminine but should I?