Place the Toro mower on a level surface, and turn off the engine. Pull the key from the ignition. Raise the hood of the Toro mower, and remove the oil fill cap and dipstick from the engine.
Pull off the protective cap from the end of the oil drain port -- on the right side of the engine. The oil filter is on the same side of the engine. Push the oil drain tube over the end of the drain port. Position a catch container on the ground, and route the open end of the drain tube over the container.
Push the drain port toward the engine, turn it counterclockwise and pull it out to allow the oil to drain from the Toro mower. Once the oil drains, push the drain tube inward, and rotate it clockwise to close the drain. Remove the oil drain tube, and wipe up any spilled oil with a rag.
Reposition the catch container under the oil filter. Grasp the filter with two hands, and rotate it counterclockwise to loosen it from the engine. Spin it counterclockwise with one hand until it releases completely from the engine. Drain the oil filter into the catch container, and discard the oil filter.