You want the stylus tip to be right in line with the edge. You can eyeball it, or you can use something like a razor blade or combination square to confirm it is in line. You want to make sure at the same time the cartridge is square in the headshell, or more precisely that the cantilever is in a straight line down the center and not angled to either side. I would think that’s going to get you pretty close with an elliptical stylus like the 2M Blue. I get a bit more fussy with my ML stylus, but even then I haven’t gone overboard (yet).