AP Lines are on the overlaps for a ROTJ style of build.
on the shins, thighs and other parts you should follow the suggestions on
peter/stukatrooper's build
for making ANH stlye builds you first cut on the lines exactly. then take off a little on the fronts of
the leg parts for the anh style.
on the biceps and forearms, cut on the faint lines, and overlap them on your arms and biceps
tape them together. and test fit them.
then mark the centerline where the parts overlap
cut off the overlaps to meet in the middle and glue with a backing strip.
when assembling the thighs you align them from the top, and then trim the bottoms after they have
been fitted together.