Basic ground: With the dark threads in the holes closest to your body, pass the weft thread. Roll all the cards away from you twice passing the weft thread each time. Now the dark threads should be in the holes farthest away from your body. Roll your cards towards you twice passing the weft each time. Switch direction every time the dark cards are in the holes closest to you, or in the holes farthest away. This will give you a solid dark top of the band and a light bottom of the band. I recommend only stopping when your cards are in the closest or farthest position so you know which way to go when you start weaving again. If you wind up stopping with the dark in your top holes, try one roll either forwards or back. If other dark threads come to the top you are rolling in the right direction. If the top threads continue to float you are going in the wrong direction.
Most tablet weaving consists of slanted threads with the slants determined by the direction it passes through the card (S or Z) as well as the turning direction. When you change turning direction the thread will lie straight rather than being slanted. Double faced weave is made up of these transitions, so the visible threads will not have a slant. These are referred to as floating threads because they are not drawn down into the weaving structure, but float above it. You can also do double face weave with your cards alternating S and Z. This will result in a different look as your weft threads will show on the ground weave.
Color changes can be done several ways. You can change the turning direction of the cards you want to become light instead of dark by flipping on the vertical axis, or you can rotate the cards two additional turns without passing the weft thread. There are some differences in structure between these methods, so sometimes one method works better than the other for specific patterns. I prefer flipping the cards on the vertical axis (from S to Z, or Z to S), because it has a cleaner transition, and is really easy for me to keep track of. When you flip a card on the vertical axis you are changing the rolling direction of that card while continuing to roll it in the same direction as the other cards. However not everyone likes flipping cards from S to Z, and giving the cards you want to change two rolls in one direction works best for some people. The way that works best for you is what you should ultimately use, but it is best to understand both ways. So we are going to try both.
When your dark threads get back to the closest position, roll your cards twice without passing the weft. I tend to continue rolling them in the direction they just rolled, but rolling the opposite direction will work as well. This will move the light threads to the front, and the dark threads to the back. Since you want the light threads to show, you will treat them the same way you treated the dark threads by rolling away from you twice while they are in the closest position passing the weft each time, or rolling twice towards you when they are in the farthest position passing the weft each time. When you want the dark threads back on the top of the band, roll your cards twice without passing the weft.
Vertical Stripes: Instead of changing the color on all cards, slide two cards from each end into a new pack without rotating them or flipping on the axis. Then on your original pack change the color on each of the remaining two end cards by rolling them twice, and shift them into a different pack. Repeat this until you run out of cards in the original position, and all are in one of the two packs. Using the outermost end cards as your guide, roll that pack in the appropriate direction to keep that color on top. The other pack will roll in the opposite direction. When your vertical stripes are to the desired length, change the color back, on the pack without the outermost end cards. Remember that the color changes need to take place while the chosen ground color (background) is in the closest or farthest position.
Squares and Rectangles: With the dark threads in the closest position, flip the desired number of center color change cards on their vertical axis. Roll the whole pack in the direction dictated by the edge cards, and the cards you flipped will now have the light color on the top of the pack. When you are ready to change back to a solid ground, flip the cards you previously flipped on their vertical axis again, while the end cards have the dark in the closest or farthest position. When you start weaving again you should have a solid dark ground.
If you want to chart your own patterns I recommend using excel. Set your column width at two for the same number of columns as you have cards, and increase your row height to 30, and you will get a pretty accurate graph of your intended design. If you have charted something complex, you can use a magnetic board to keep track of where you are in a pattern.
Some basic patterns I doodled in excel for the class handout, all should work on a 20 card width. Sadly, I can't figure out how to take the gridlines with me.