Here are some cheap and easy DIY ideas for organizing your closet: https://www.lifestorage.com/blog/organization/easy-diy-closet-organization-budget/
The first rule is to purge ruthlessly. It is estimated people wear only 10-20% of the clothes they already own. Take everything out of the closet to determine exactly what you have. If you haven’t worn it in the last 6 months, get rid of it. Maybe you can consign or sell on-line some of the current styles.
Once you’ve purged the excess, check out Pintrest for organization ideas. A word of caution though…Pintrest can suck you in for hours just to look at pretty things. Trust me, I’ve been there for hours at a time looking for “just one thing”.
I have mine by weight and color. For example: sweater, long sleeves, short sleeves, tank tops. Work out clothes are hung in a small area together. Your lifestyle will dictate the way you organize. Since I work in an office, my professional attire takes over the majority of my closet space.