Hecarim vs Riven

From the perspective of Hecarim, I just can't seem to understand how to win against Riven. He's listed as a counter, but even playing the matchup how I had believed to be right, I only win half of the lanes. I'm aware of mechanics like using E to kick her third Q, negating the knock up and damage. You outsustain her if you're able to use your W within the minion wave. And you can take advantage of her more significant cooldowns in the early game before she builds CDR. My best idea to improve my success is to try to play less of a fight lane. Push the wave until you can force her cooldowns. She doesn't push as hard as you can early, so continue to push once she's used her abilities. If you're able to get her under turret, then she has to use her abilities to CS under tower. Any helpful advice is much appreciated. Thank you in advance :)

P.S. I'm only worried about the early lane against her. Post level 6 I like to roam a lot and tend to have much greater map pressure than most Rivens I've faced.