This is the first twenty cards from Phiala's pattern. The set up is still the same, except doubled. So it is 40 cards wide instead of 20. It's the basic diamond set up, without any cards flipped from S to Z. Instead half the cards will roll backwards (which is actually the same thing). Because it uses four colors instead of 2, you will only have two options for a diamond color unless you shift the cards to bring the other two colors together in the center. If you want to change to the other color options simply pack 2 twice in the same direction, repeating the double roll with pack 4. Packs 1 and 3 will not roll. If you do this in the middle of your piece it will be obvious, so I recommend sticking with one color set.
Roll the first ten cards towards your body, leaving them separate from the original pack. Roll the next ten cards away from your body. Repeat with the next two sets of ten cards. You should now have four working packs in two lines. Pack three will do the same as pack 1, and pack 4 will do the same as pack 2. The cards closest to your body will roll towards your body, the cards farthest away will roll away from your body. When you weave this you will get two rows of side by side inverted chevrons. Do this until you have the desired number of chevrons in your chosen color. I will refer to this as orange so it matches the pictures. I did all pattern changes at the 3rd chevron. When the two orange threads reach the center point of the chevrons, you are ready to start the diamonds. Roll only 9 cards towards you, and roll the remaining card away from you. On the next pack roll the first card towards you, then the remaining cards away from you. Repeat with packs 3 and 4. As you can hopefully see from the picture, I let the cards stay offset to make it easier for me to keep track of them.
The orange threads should begin to float.
Next on the 1st pack, roll 8 cards towards you, the next one away from you, and the final one towards you again. On the 2nd pack roll the first card away from you, the next towards you, and the remainder away from you. Repeat with packs 3 and 4. The photo below shows my offset cards between packs 3 and 4.
The floats are getting wider.
Now comes the hardest part to keep track of. You will be reversing what you just did. On the 1st pack roll the first 8 cards away from you. Roll card 9 towards you and join it back into the 8 cards. Roll card 10 away, and leave it offset. On the 2nd pack, roll card 11 backwards, leaving it offset. Roll card 12 forwards, and roll the remainder backwards joining them to card 12. Repeat this for packs 3 and 4. This should result in the end floats being brought back into the regular weave.
On the 1st pack, roll cards 1-9 away from you, 10 towards you, and join it into the pack. On the 2nd pack 11 rolls away from you, while 12-20 roll towards you. Once again becoming a single pack. Repeat with packs 3 and 4. You should have 4 packs with no cards offset. Now roll pack 1 away from you and move it to the further away position. Roll pack 2 towards you, moving it to the closer position. Repeat with packs 3 and 4. The positions of the pack have been reversed, but packs close to you still roll towards you, and packs further away still roll away from you. Weaving this should now result in regular chevrons. Continue weaving until you have the same number of chevrons you had before starting the tiny diamonds. Then change the rolling direction of each of the packs, once again shifting them in position. This means that pack 1 will roll towards you, and move closest to you, and pack 2 will roll away and move furthest from you. You are now back at the beginning of the pattern, and weaving should result in inverted chevrons.
You can fill in the open diamond in the center where you changed direction, or you can change color on any of the diamonds, by repeating the same process except using the opposite corner color.
Just for grins and giggles this is what the back looks like: