The present application discloses a method of forming a hydrogel-coated substrate, wherein the hydrogel has antifouling and antimicrobial properties. The method comprises applying an aqueous pre-hydrogel solution to a substrate, polymerizing the aqueous pre-hydrogel solution, thereby forming a coated substrate having a conformal hydrogel coating and a non-conformal hydrogel coating, contacting the coated substrate with a swelling agent, and removing the non-conformal hydrogel coating from the coated substrate, thereby leaving the conformal hydrogel coating on the substrate to form the hydrogel-coated substrate. The aqueous pre-hydrogel solution comprises a monomer with antimicrobial activity, a monomer with antifouling activity, and either a polymer, oligomer, or macromer which, when polymerized together, form a hydrogel. Also disclosed is a coated substrate and a hydrogel coating.