Understanding Brain Freeze

From a PvP point of view how can I maximize my BF proc's?? Is it proc'ing mostly from my frostbolt casts??
You have two "frost damage spells that have a slow affect." They are frostbolt and cone of cold. I would say that using BF as an instant cast but not under the affects of FoF (and using every FoF charge for IL) would be an ideal use, as instant casts are where it's at and trying to cast another frostbolt can be hard or even impossible in many situations.