I suggest riding at least a third of the way out into the lane.
This will improve your visibility to motorists, and it will encourage them to cross into the other lane to pass you. I have found that if I am far to the right, motorists will try to pass me while staying in the lane or when cars are oncoming in the other lane. This results in a close and dangerous pass.
By moving farther out, it forces the driver to cross the yellow line, and I have found that in most cases, once motorists commit to crossing, they tend to go really far over the yellow line.