The present methods provide an amorphous, conformal, protective, abrasion-resistant, lubricious fluoropolymer coating on to a polymer substrate via a gas plasma deposition method. The coating method, according to one embodiment of the method, involves generating a gas plasma by introducing a mixture of a fluorinated gas monomer and a hydrocarbon gas into an energetic ion field, such as an ion beam or the field produced by a radio-frequency source. The fluorinated gas monomer is selected from the group consisting of CF.sub.4, C.sub.2 F.sub.4, C.sub.2 F.sub.6, CF.sub.3.sub.2CO, CH.sub.2 CF.sub.2 and mixtures of the foregoing. The hydrocarbon gas is selected from the group consisting of C.sub.2 H.sub.2, C.sub.2 H.sub.4, C.sub.2 H.sub.6, and H.sub.2 and mixtures of the foregoing. The polymer substrate is exposed to the foregoing gas plasma for sufficient time to achieve the desired coating thickness.