Demonstration: /ˌdɛmənˈstreɪʃn/ an act of showing that something exists or is true by giving proof or evidence.
Plenty to show and tell this evening with some great kits on display..
Basically: Prime part to be rusted, apply rust color(s), then seal with matte varnish, then spray with hairspray (other methods can be used, salt etc) then apply the coat of paint that is to be eventually chipped away. Once dry wash with warm water then slowly chip away at the paint to reveal the rust colour underneath. Once happy with the effect seal with matte varnish then start applying your pigments, washes etc to achieve the desired effects.