Instructions
Train your cockatiel to get onto your finger first if he doesn't already do this. Place your index finger crosswise in front of the bird, lightly touching his chest and say the word "up." At the same time gently push your extended finger back and up into his chest. This will cause him to loose his balance and step onto your finger.
Repeat the steps above to get your bird onto your finger until she has that lesson mastered. After doing this several times, she will learn to step onto your finger whenever you say the word "up."
Extend your arm straight out away from your body while your cockatiel is standing on your finger. Many cockatiels will take that as an invitation to run up your arm and when they get to your head they will settle on your shoulder on their own.
Place the cockatiel on your shoulder if she doesn't run up your arm on her own. If you want her to come to your shoulder on command, then give a verbal command such as "shoulder" every time you place her on your shoulder.
Continue placing your cockatiel onto your shoulder every time you are ready to spend time with him. Soon he will realize that a shoulder is a fun place to ride and he will find his favorite perch on his own.
How to Shoulder Train a Cockatiel
Most socialized cockatiels will enjoy riding on your shoulder. They are lightweight and small enough in size, that having them ride on your shoulder is a often a good way to spend time with your bird friend. Some cockatiels will get on your shoulder on their own, others might need a little training.