This is the one-pack method for 3/1 Twill using four of the same color threads in each pattern card, and two border cards on each side which move independent of the pattern cards.
Rotations for the 12 pattern cards (all threaded S or Z):
2 F, 2B repeated for the entire line
1 F, 2B, then repeat 2 F, 2B for the rest of the line
2 B, 2 F repeated for the entire line
1 B, 2F, then repeat 2B, 2F for the rest of the line
Ready to start, with border cards shifted away from the body (will be rolling in that direction, until it gets tight, then flipped on the vertical axis, so they can continue rolling the same direction but remove twist buildup).
End of the first row (2 F, 2B repeated for the entire line). The direction turned will naturally offset the cards, until you move them back into a single pack.
Shifted into one pack, except for the first card which indicates which line you are on. 1st card will roll away from you, so it must be row 2 (1 F, 2B, then repeat 2 F, 2B for the rest of the line).
Forgot to take a picture of the end placement on row four, but hopefully it is not needed.