I usually try to fly at odd heights (not a problem, really, given my apparent inability to hold altitude for more than a few seconds at a time
) to avoid the likelihood of finding someone else at my level. That and a constant lookout, including moving the nose around once in a while to have a look under it, pretty much do the trick.
It might help that straight and level bores the hell out of me so I'm usually up to something, even on a cross country, even if it's just butter-churning the stick a bit. It breaks the monotony of a boring flight and helps me keep a good lookout because my scan territory is always changing.
Pitts2112