Removing earrings is safest. For conservative industries, don't wear earrings. Observe other men in your industry to see what is acceptable. If you wear pants, they should be creased and tailored, not tight or flowing. If you are pursuing a conservative industry and are in doubt, observe well dressed women in your industry on the job, at career fairs, at information sessions, etc.
Skirt lengths come and go.
Before choosing a skirt to wear, sit down in it facing a mirror. That's what your interviewer will see. Ask yourself whether it will be distracting or reinforce your image as a person who looks appropriate for a business environment or gathering. Women generally have more options with suit color than men. For example, while a women could look conservative in a slate blue or light gray suit, these colors would be inappropriate for men.