To start, take your sleeve pattern and front pattern piece.
Match the front underarm point on the bodice with the front underarm point on the sleeve (in some cases this will mean flipping one of your pattern pieces upside-down so that the points are on the same side).
To start, match the underarm points of both pieces (the points we found in the previous step) by laying the sleeve pattern onto the front pattern.
If you are using a pattern that has seam allowance, be sure to match these points on the stitching line and not on the edge of the pattern.
The seams should line up for a centimetre or so, before the curves begin to change course.
Take a stiletto or a pin and place it on the point where the change occurs.
The stiletto will hold the patterns in place so that you can rotate the sleeve.
Pivot the sleeve into the armhole as if you are sewing the seams together (be sure to hold the bodice pattern in place, while you move only the sleeve). Turn the sleeve pattern until the seams are in line with each other again.
Once the seams line up, stop and move the point of the stiletto to the end of the section.
Now pivot the sleeve from this new point.
Continue "walking" the sleeve cap into the armhole until you get to the front sleeve notch.
When you reach the sleeve notch, hold the patterns in place and transfer the location of the sleeve notch onto the armhole underneath with a pencil or tracing wheel.
Continue "walking" the sleeve into the armhole from the notch.
Continue the process until the sleeve meets the shoulder seam of the front pattern.
Mark this point with a notch on the sleeve pattern (use a pencil as this is a temporary notch).
Now move onto the back armhole.
As with the front, take the back underarm point on the sleeve and match it with the underarm point on the back pattern.
As you did with the front armhole, walk the sleeve in, until you reach the double notch on the sleeve,
Transfer notches onto back armhole.
Continue pivoting sleeve until it reaches the back shoulder seam.
Mark this point on the sleeve with a notch (use a pencil as this is a temporary notch).
Measure the distance between the temporary notches. This distance is the amount of ease there is in the sleeve cap (the difference between the length of the armhole and the length of the sleeve cap).
The amount of ease needed in the sleeve cap depends on a number of factors - the type of fabric you will be using (for example, jersey won't need any ease in the pattern as it can be stretched into the armhole, although woven fabrics will need some ease) as well as the style of sleeve. The further the shoulder extends beyond the natural shoulder point, the less ease required in the sleeve cap. This is because the sleeve cap is no longer on the shoulder point (where there needs to be ease for comfort and movement of the arm) but on the forearm.
In the next tutorial I will walk through how to increase and decrease the amount of ease in the sleeve cap if you are not satisfied with the amount of ease in the cap at this point.
At this point, you will also need to locate the shoulder point. Simply mark the point halfway between the notches - this is the shoulder point (it may or may not lie on the grainline of the pattern).