The Closet Pitch -

: Install a deep shelf at the bottom (around 36 inches wide) and progressively narrower shelves as you move up the slope.

: Use custom board dividers or modular systems to prevent items from sliding toward the lower end of the slope. The Closet Pitch

Depending on your skill level, you can build a custom solution or adapt existing products. How to optimize a built-in wardrobe with a pitched roof? : Install a deep shelf at the bottom

: Place hanging rods under the tallest part of the slope. For long items like gowns or coats, aim for about 68 inches of vertical space. The Closet Pitch

Before buying materials, you must determine the exact degree of the slope.