Grappler, the De La Riva guard is all over the place these days and it's easy to get ahead of yourself and skip a few steps to get to the really fancy, trick techniques that will get you the chicks (the hot ones). But, it's wise to slow down and first get down the initial basic sweeps from a standard DLR position. Case in point - the video below from our brothers at Phuket Top Team. This technique for a a basic trip-type sweep from a DLR is properly demo'd by Prof. Olavo Abreu, Head BJJ trainer at PTT in Thailand.
So, get yer learn on. This one is doable right off the bat (after a few drilling sessions).