oldie but goodie:
I've had excellent luck using an old turkey pan and cutting it up to fit under/around the bottom of the filter. Since those only come around once a year or so, I use just aluminum foil most of the time. Gets the oil out the left side of the bike no problem.
More importantly, I think, is after putting in whatever pan you use under the filter, I make 2 small openings in the end of the filter, either with the tip of a screwdriver or a sharp punch. One towards the bottom for oil to drain out and another near the top for air to get in. That way any oil in the filter gets drained out before you even remove the filter. Very clean and neat, and I like that!!!
Jer