Like Hawg I use a long strip of patch material (pillow ticking, cut into strips 1 1/4" wide, soaked with 1:6 ratio of Ballistol to water and dried); lay the end of the strip across the muzzle, set the ball on top of the material and start it into the muzzle with my thumb, use a ball starter to push it in until it's flush with the muzzle, hold the strip tight and cut across the muzzle with a very sharp patch knife. I then use the ball starter to ram it down a couple of inches and finish with a solid brass range rod.
Never thought about excess patch material in front of the ball. Seems to me it would get pushed out of the way. But, as Hawg said, seating the ball flush with the end and cutting across the muzzle pretty much cleans it up anyway.