Use T-connectors to attach eight 5-foot sections of PVC pipe together, so that you have one 40-foot section. Repeat this until you have a total of four 40-foot sections of PVC.
Use a T-connector to attach two 7-foot sections of PVC pipe. Repeat this until you end up with four 14-foot sections of PVC pipe, each section secured with a T-connector in its center.
Use the 14-foot and the 40-foot sections of PVC to create two large rectangles. Use three-way corner connectors to secure them together at the corners.
Insert one 6-foot length of PVC upright into each upward-facing connector opening that remains. At the top of each 6-foot section of PVC, place a four-way connector. Following the contour of the rectangles below, make sure that you place corner-shaped connectors at each corner.
Fit PVC pipe pieces in between each connector in order to create another rectangle. Repeat Step 4 here by placing another section of 6-foot PVC piping upright into each connector opening. Use the remaining rectangle that was built during Step 3 to place on top of the entire assembly to finish the frame of the cage.
Drape baseball cage netting over the cage and let it hang loosely. Secure the netting in place by using zip ties to attach the netting to the PVC piping every few inches. Remember to let the net drape somewhat loosely.