Directional flow refers to a technique used when pressing rosin that involves carefully folding parchment paper placed inside the press over the plant material to intentionally control and direct the flow of extracted oil into a centralized collector region instead of allowing it to spread and ooze out messily in all directions. The paper gets folded up into an envelope or pouch shape with interior creases and channels purposely guiding and leading runoff to drain toward one bottom corner. When compressed under extreme pressure, the extracted rosin automatically travels downward along these preformed paper folds and seams based on gravity rather than seeping randomly outward across the paper. Directional flow effectively contains the oil for the most efficient yields possible. Besides improving yields, channeling the extract through guided folds also keeps the entire mechanical pressing process far tidier overall. No precious rosin gets wasted by being stuck in the metal plates or splattered outward making a sticky mess. The simple parchment paper origami technique makes rosin collection much cleaner and more efficient with minimal loss. While seemingly trivial, establishing a focused directional oil flow makes a substantial visible difference.