Pour 4 to 6 ounces of chilled Fresita into the wine glass, which should be a large one (an 8 ounce or larger glass works well). Pour 1.5 ounces of chilled vodka into a small shot glass. Pick up the wine glass in one hand, and the shot glass of vodka in the other. Carefully (well - do your best) drop the shot glass bottom-down into the wine glass, trying not to "spill" the vodka. Then drink off the entire contents in one go. The vodka will spill into the Fresita as the glass drains.