One easy trick is to KEEP THE CENTERLINE OF THE ROAD NEXT TO YOU, THE DRIVER.

This helps especially if you get confused turning in an intersection. And if you pull over to look at a roadsign, concentrate on getting back into the proper lane when you pull out. You have no idea how many times I got into an impromptu game of chicken when I would look at a sign, then without thinking, I'd pull back into traffic into the wrong lane.

Roundabouts - Staty in outer lane if you're taking the next turnoff, otherwise go into the inside lane if you're going past more than one exit, then getting into the outer lane before your intended turnoff. Staying in the outer lane all the way around annoys the natives mightily...