The first step is trimming. This will allow you to overlap the edges of the pattern pages correctly. From every page trim off the right and top margins.
Remember to use different scissors for cutting paper than your sewing scissors.
Once all the pattern pages are trimmed start assembling them together. The pattern pages are numbered to help you figure out the correct order. Line up the triangular marks and all pattern lines and use either clear tape or glue stick to put the pages together, always making sure that you are lining up the edges straight.
After all the pages are taped or glued together, cut out the pattern pieces.