Take in air on count 4 (after breathing mark) and close lip by saying "UP". Then try to make a buzz with the lips by using the sound POO. Keep the tongue down and use the syllable P. Try to hit a low C. The pitch is not important here. It is more important to aim for an relaxed buzz. Be very exact with the rhythm. On the repeat, use TOO attack, with tip of tonguet. Repeat 3 times more with TOO - attack.