BumpyBall is a 5v5 multiplayer game in which you drive around in a car on a soccer field while trying to knock a ball into a goal. Yes, it's Rocket League - with really cool grass physics.
As is the case with most driving games, accelerate with "w", go backwards with "s", and steer left or right with "a" and "d". Boost with the space bar.
Teamwork. That's really the only strategy you need, but it's also worth mentioning that the crates littered about the field will regenerate your boost meter. A well-timed double boost can mean the difference between sinking the goal and sinking your chances at a win.