Then curve the hands around the front of the joint and press the keys so that the bridge mechanism opens or lifts. Doing this allows you to slip the lower joint bridge key under the upper joint bridge key. Now hold the lower joint in the proper hand, toward the lower end of the joint, with no extreme force on the keys or rods. Make sure that every one corks are sufficiently lubricated with cork grease. Twist the joints together in a back andforth motion, as opposed to by turning the lower joint in a round motion. The joints should slide smoothly together, and the rings in the front may be in line. After inserting the upper and lower joints together, twist the bell into place and then the barrel. The barrel has a small and a large end, and though it is doubtless obvious to you, make sure that your youngest students place the barrel on in the correct direction, with the bigger side of the barrel becoming onto the higher joint. Finally, place the mouthpiece on the barrel, and then the ligature and reed, in that order. Remember to keep the tenons well greased with good, clean cork grease, but do not allow too much of it to building up on the cork. Instead, wipe excess grease off before making use of more so that it doesn't get sticky.