For colder conditions you want to dress in layers. For your base layer polyester or fleece long under wear is best. No cotton as it loses its insulating properties once wet. For your insulating layer wool or fleece is ideal as it can get wet and still insulate. For your external layer you want something like Gortex to shed water and stop the wind.
For footwear: in colder conditions wear wool socks and tight fitting shoes such as tennis shoes. If you have neoprene booties then water those. In warmer conditions wear tight fitting shoes such as tennis shoes or sandals that have a strap across the back so they stay one. Flip flops are a poor choice as they can easily fall off and be lost.