Waves raise yellow float and the latter falls due to its weight. These motions make orange output shaft rotate one way.
In this video the grey bearings are stationary. However they can be installed on another float (not shown). The distance between the two floats is chosen to be about equal to half of the wavelength. Thus the oscillation angle of the yellow bar can be increased. The second float also helps the motor adapt to variable sea level caused by the tide.
Several such motors are connected in series (coaxial connection of the orange shafts) to increase output power. The output rotation after being accelerated and evened out is transmitted to an electric generator.