1: Open the editor.
2: Place one or more FIA men.
3: Insert into the init box of each unit something like "this addHeadgear 'H_Milcap_dgtl'; this addGoggles 'G_Combat';", which should give him an AAF officer's cap and combat goggles, replacing whatever head- and face-wear he would normally have.
4: Preview. Note that the men do not initialize with the AAF officer's cap and combat goggles, they having been replaced with a random combination post-initialization.