Please, don't whip out the spray tanner. We're talking about outfitting her for the occasion. Women are fashion-motivated, so producing a personalized jersey prior to the playoff game might entice her to muster some new-found fanaticism.
Plus, have you seen the way women look in snug, shrunken jerseys? The investment is undoubtedly a gift that will keep on giving, and may even inspire some fresh fascination with your newly-minted fan girl.