I go to youtube for defenseman advice/help.
One thing that improved my defensive play (since there's no checking in the league I play in), is the concept of "stick on puck". This helped a lot. By keeping my blade near the puck-carrier's puck, if he passes or shoots the puck, my blade would block or redirect the puck. This prevented a lot of pass plays, took away puck possession or blocked a shot on net. This does nothing if he can dangle around you and avoid your poke checks.
Defensemen need to work together, so it can't be just you vs. him. If he's on the ice, then you need proactively play defensive and start moving back when he touches the puck, particularly if he likes to break away on his own. This will take away a possible pass, if any of his teammates like to join him on the break out. If it's two-on-one and he's got the puck, cover the open man and let the goalie take the shot. Or if it's two-on-one and he's the open man, cover him and let the goalie take the shot from the other guy.