First of all, make sure you're using a spinning-friendly line, i.e., low memory, easy handling, etc.
Check the owner's manual. Some reels with anti-twist line rollers recommend holding the supply spool up and down like a baitcaster. This works on these reels, but the traditional way works too.
As for the traditional way, every time your reel spool turns, a clockwise twist is put in the line. The idea is to have a counterclockwise twist coming off the supply spool to offset, or partially offset, the clockwise twist. This means the supply spool is on the floor or other flat surface such that the line comes off counterclockwise.
Ignore the label position. It has nothing to do with the physics of line spooling and is unreliable. I have in my possession two sizes of Trilene XL with opposite label positions and this has been my experience for years, with other brands as well.
Finally, all other things being equal, best line performance comes when you have line on a relatively large reel spool. By this I mean avoiding things like 10 or 12# line line on a reel rated for 4-6-8.
Good luck.