You will want to start out with a piece of maille made in the horizontal fashion. Even if you plan to make your sheets using this method, the first step is to make a piece of maille with 3 rows horizontally. As before, you can make them as long as you like. Then turn it 90 degrees such that it looks like this:
This may seem a little familiar, but pay attention to the orientation of the links. Open a link and place it through the two lowermost, leftmost links. Add two closed links to the open link and close it, then lay your work out as shown in the last frame.
Open a link and insert it into the weave as shown. Then add a closed link to the open link, close it, and lay the work out. See how similar the two methods are?
The pattern should now be apparent - Add an open link, add a closed link to it, and close the open link. It's like deja vu all over again!
Repeat until you get to the end of the row
Great! Now given a piece of euro 4 in 1 mail, you can expand it in both the vertical and horizontal directions and make a sheet of whatever size you require.