Step 1: Soak your reed. Rub a small amount of cork grease on all corks, if needed. Clean hands.
Step 2: Hold the upper section near the top with your left hand. Grasp the lower section with your right hand, holding it near the bottom. Gently twist the upper and lower sections together. The upper section's bridge key(s) must be directly over the lower section's bridge key(s).
Step 3: Hold the instrument near the top of the upper section with your left hand. Grasp the bell with your right hand. Press down on the round bell key, raising it. Twist the bell onto the cork of the lower section. The bell bridge key must be directly over the bottom bridge key.
Step 4: Put the reed in your mouth. Form your embouchure and blow forcefully through the reed to remove excess water. Carefully insert the cork of the reed all the way into the reed well on the upper section.
Step 5: Put your thumb under the thumb rest. Place your left thumb just below the octave key. Your fingers should curve naturally. Hold the oboe as shown above.