A simple way to transfer seamline markings from pattern to fabric is by notching the pattern's corners through all fabric layers underneath. This technique is used by more advanced dressmakers and rather then transferring the whole seamline, the notches serve as an impression of the seamline's beginning and end.
These corner slits serve as a wya to mark the designated seam allowance width along each fabric edge which can then be used to correctly align the seam edges to the appropriate seam allowance guid eon your sewing machine. The notch located at the top and bottom of each seam is aligned with the machine needle which naturally positioned the seam edges correctly in the stitching process- the rest is a simple process of following machine guides accurately and evenly throughout the stitching process.
To use this marking technique, start by slashing halfway through the seam allowance of an intersecting seamline at the corner through both paper pattern and all fabric layers underneath. Some patterns will provide an intersecting line that provides a stop point for the slash- these intersecting lines are called "T" notches are commonly used at the factory level and in the manufacturing world to mark seamlines and other seam alignment notches.
Using this simple slash notch, the vertical seam allowance width will be recorded on the fabric pieces underneath. In this case, the seam allowance is 1/2".
Next, clip another notch on the intersecting seamline to record the horizontal seam allowance. The fabric layers should now have two separate notches marking the designated seam allowance along the vertical and intersecting horizontal edge.
When finally stitching the seam, the slash notches are aligned with the machine needle which naturally aligns the fabric edge to the corresponding seam allowance guide on your sewing machine. If you already feel comfortable with your sewing ,machine and can stitch a seam evenly by following only the seam allowance guides, you can really benefit from this corner seamline transfer technique as it will save you the trouble of double -checking your patterns for seam allowance width reminders.
If you take a look at the finished seam, the stitch line should start and end exactly where the notches are at each corner. The rest of the stitch should be positioned evenly, at the seam distance from the edge throughout.