Is it possible to make curves more visible in the 3D view? I'm trying to edit a camera path and a camera follow path, but I'm finding it quite hard to see the curves. Is there a way to change their color or make them thicker? I've also seen screenshots that show frame numbers along the curves—how do I enable that?
Just as Mr Zak suggested, you can give the curve in question a bevel object. You can adjust the thickness of the curve by scaling it.

Just switch off render for both of them and it shouldn't affect your scene.