Matt Darcy shows an entree into the single leg by posting on their chest making their front leg light. This entry is especially useful in situations where you may not want to get into grip fighting with your opponent or for the use in nogi.
In this video Matt Darcy shows some drills to develop the proper timing for basic kouchi gari.
This kids fundamentals series focuses on teaching the required techniques in a digestible way for our young white, grey/white, and grey belts.