Purse your lips to form an exaggerated kiss. Open them just enough to allow you to breathe in through your mouth.
Place your index finger in front of your lips, pointing upward.
Speak while inhaling. Experiment with different words to achieve a turntable-scratch sound. Most beatboxers use syllables like "too," "too-eee" and "too-kee."
Experiment with low and high pitches as well as the length of your sounds. A high-pitched, inhaled whistle can produce a scratching sound by saying "hoooooooo-eet."
Cup your other hand over your mouth if you don't have a microphone to enhance the sound.