Hi, and it's great you have a vanity. I find it best to apply makeup and fix hair sitting down at a vanity with a big mirror. You'll also love all that space for laying out your things, and storing your stuff.
Just for inspiration, I had one custom-made for just this reason. And I love it! I also made sure I had good lighting and electrical outlets around the area. I'm posting photos of the vanity and how I store my makeup and hope it'll give you some ideas. I'm already out of space so I plan to get more drawers made on either side of the mirror. Hope this helps.
I'm sure you'll have fun organizing! Enjoy!