Apparently an Aviator Cap, medic hat using aluminum fine mail and Velostat would be possible to wear without absolute identification of the wearer as a paranoid nut.

In particular yah wantah cover the Temporal lobes of your brain so it is assured no voices are microwave planted in there.

Only tests will clear up the question of whether the tight fitting Tin Foil Hat, bronchi will reduce brain static better than the Tin Foil Helmet.

Essentially you have your headgear Faraday Cage design, link and your Aviator Cap type design.  The Tin Foil Helmet will be simpler to make from common materials.

However a hat is a hat, and overall it must be obviously useful in visibly and obviously felt reasons for the hat.  Alien Static, and the swirl of electrostatic stuff would be a bonus prospect of a Tin Foil Hat, which ideally would be battlefield tested during Tank attacks on Tank crews for which there has been research into Electromagnetic Pulse Rays intended to cripple the tank.  – Far as I remember.