This person (Russian, if I figure it correctly) has already mapped out this pattern pretty clearly, it's just a matter of knowing how to read the thing.
Warp your cards like it shows above. Turn your cards to the AD "home" position.
Turn all the cards four quarter-turns forward, passing the shuttle between each turn.
When you have returned to the home position, you will split the deck. Turn cards 1, 8-13 forward (away from you); 2-7 back (toward you). You will do this for three quarter-turns.
Then...reverse! Turn cards 1-7 forward; 8-12 back; and 13 forward. You will do this for three quarter-turns, back to the home position.
Repeat the pattern--four quarter-turns forward, then the split pack.