Thousands of players go passively for offensive rebounds, and coaches often let players get away with that passive effort. Perhaps the reason is that defensive rebounds are expected, or easier to get. But in most cases, the reason more offensive rebounds are not grabbed is simply that players don't try hard enough to get them.
Get to the HOT SPOT especially from the opposite wing of the shot.
If you are stopped by contact … spin.
Go get the ball. Get noticed.