Step 2. Lay your pattern piece on your fabric and mark the intersections of the stripes.
Next, lay your pattern piece on the fabric where you plan to cut it.
It is very important to ensure that your fabric is perfectly flat, straight and without any diagonal distortion.
Use a colored pencil to mark where the stripe or plaid crosses the seam line. In this case, I traced between the orange and pink stripes in a few different places on the pattern piece.
Do not trace the line to the edge of the pattern piece, but only to the seam line as shown.