The couple standing in this walk-in are not posing in front of a showroom display, they are standing in the middle of a negotiation that ended well. Look past the smiles and you will see the terms: matching wooden shelving on both walls, a hanging rod at the same height on each side, and enough breathing room between them to open a drawer without stepping on anyone's shoes. That is the whole secret of a his-and-hers closet. Not more space, but evenly divided space.
Start by measuring what each person actually owns, not what the internet says they should own. Count the longest dress, the longest coat, and the tallest boot, then set the rods and shelves so both collections fit without anyone's hems dragging on a shelf below. In a symmetrical layout like this one, the eye reads fairness instantly: two runs of shelving framing a soft rug, two stacks of folded knitwear, two rows of footwear lined up at the bottom where they are easy to grab. Where the wardrobe is asymmetrical in real life, say one person has twenty pairs of shoes and the other has four, give the shoe lover a taller bank of low shelves and balance the visual weight with folded linens or baskets on the other side.
Drawers deserve the same respect as hanging space. Put his-and-hers drawer stacks at equal heights so nobody is crouching while the other stands comfortably, and give each person a full set rather than splitting one column down the middle. Dividers inside keep folded tees from turning into a pile, and a shallow top drawer on each side is the natural home for watches, belts, and the small daily things that otherwise migrate to the kitchen counter.
The details that make a shared closet feel calm are almost always shared ones. A bench or low ottoman in the center gives both people somewhere to sit while pulling on boots. One laundry basket per person prevents the quiet resentment of a hamper that is always full of someone else's shirts. Soft light matters more than most people expect, so keep sheer curtains on any window and add warm bulbs rather than cool white ones, because nothing looks less appealing than a beautiful wardrobe lit like a fitting room.
Finally, build in a seasonal reset. Twice a year, both of you pull out what you did not wear and move it to storage up high or out of the room entirely. The shelves stay airy, the rods stay easy to slide, and the closet keeps the feeling in this photograph: two people with room to breathe, standing together in a space that belongs equally to both of them.