I dressed these pants up super summery here, with white sandals and a white flowy sleeveless top, but I found that with with a sweater and floppy wool hat (especially in dark and cozy hues, like black and navy) these pants can be transitioned right into Autumn.
Pants: Old Navy
Hat: H&M
Sunglasses: Aldo
Bag: Zara
Shoes: Call It Spring