From a natural posture, Tori moves forward as if to attack. Because one tends to move backwards without realizing it when preparing for a sacrifice Waza, it's advisable to move forward first, then wait for Uke retaliatory forward motion, thus concealing the Waza from him.
By moving forward in this manner and destabilizing Uke toward the back corner, Uke feels threatened, and begins to advance. At that moment, Tori pulls Uke toward the front corner on the advancing side , thus destabilizing Uke. Uke can be more effectively destabilized by pulling him forward as his body weight advances.
With legs extended, Tori then slides to the outer side of Uke advancing foot, while dropping his hips to the floor. Tori twists his body in his Hiki-te (Pulling hand) direction and throws Uke down laterally.
When performing the sliding motion, Tori places one leg against the floor and hooks Uke ankle in the crook of his knee, destabilizing him as the throw is executed. The Yoko-otoshi (Side drop) Waza is often executed from a stance in which both combatants are in defensive postures.