In the clip below Colorado State Assistant Coach Karim Abdel Waheb demonstrates three drills that will definitely help your hurdlers to develop the proper mechanics with both the take off and lead legs.
The first drill is the Cut Step into Tight Lead, designed to train the take off leg to go down and back without block your speed. It also trains the athlete to lead with the knee on the lead leg. A Hurdle Take Simulation Drill will allow the athlete to practice the cut step and lead leg continuously. The final drill is the Snap Drill. Here the emphasis is on using the speed of the trail leg to push off and start the re-acceleration phase.
For more ideas about how to train your hurdlers click on the link Curriculum Guide for the Hurdles
The YouTube video has sound, so please make sure your sound is turned on and that you have access to the site.