For a trendy spin on casual I swapped out the usual simple black leggings for faux leather jeggings with my flannel shirt. The sheen of the trendy faux leather helped dress up the outfit a little bit (since clearly flannel and a teeshirt with leggings is a lazy, comfy go-to) and the heel on the booties enhanced that vibe too. That way I can be perfectly comfy without looking "lazy." Just a little upgrade-trade or adding a trendy touch can make even your favorite simple outfit that much more chic.
Faux leather jeggings: H&M (similar). Tshirt: Ruche, last seen here! Flannel: Rails (similar). Booties: Steve Madden via TJ Maxx (this season's version).