コートを探してます。背が低いので、丈は短めで、なるべくすっきりしたデザインのものを。

。、、。

I'm looking for a coat. I'm short, so I'd like something with a short hemline and as clean-cut a design as possible.

Literal

Coat [obj-を] looking-for [progressive-てます]. Height [subj-が] low [because-ので], hem [topic-は] short-ish [and-で], as-possible neat design [gen-の] thing [obj-を].

探してます is the casual contraction of 探しています. 短め uses the suffix ~め 'on the X side / -ish' for approximate degree. すっきりした 'clean / neat / streamlined' is a mimetic-derived adjective. ものを at the end trails off — the request is left implicit (understood as '...I'd like / please show me'). Natural shopping register.