Find the paper you wish to make into a flower and cut a strip. Mine was about 7 inches long and 1/2" wide. Try different lengths and widths for whatever size flower you want. Take your strip and begin folding back and forth with your fingers to make pleats. You may also choose to score the pleats. My strip is 1/2" wide and the pleats are approx. 1/4" (I wanted a smaller flower). Don't worry if the pleats don't line up exactly; close enough is good. You won't be able to tell once you make the flower.
Click to Enlarge Paper Strip
Click to Enlarge Folded Pleating
Click to Enlarge Pleating