Shorts already tend to have a casual look about them, and this can be even more true when dealing with certain fabrics. Linen is such a fabric, sine it is often associated with beach-wear. It’s a fabric that usually comes in light colors such as beige or tan, so that it can keep you cooler by reflecting the sun’s rays. Linen gets wrinkled easily, but a certain amount of wrinkling is perfectly acceptable when dealing with casual wear.
Two typical examples – I find these very nice:
Beach linen shorts for women pictured:
Left: 4our Dreamers Women’s Drawstring Linen Short, natural
Right: Orvis Women’s Bright Linen Knit-waist Shorts / Bright Linen Knit-waist Short, oatmeal