The presser foot will need to be adjusted any time you significantly change the thickness of the material you’re sewing on. With caps, adjusting the presser foot is a little different than with flat goods. Because they cap flags (bounces) and has a seam, it is often best to set the presser foot to a standard setting and adjust from there.
Make sure the machine is stopped. Adjust the presser foot by rotating the adjustment gear counter clockwise until it can no longer rotate. This will take the presser foot to the lowest position possible. This can be accomplished with the needle at head up (default position) or at bottom center (as described in the adjusting the presser foot section).
If the needle is not at the presser foot adjustment point, the presser foot will not appear to move. Even if the needle is at the adjustment point, it may be difficult to see a change in the presser foot. The material of the cap is pressing up against it and you may not see it lift off the material. This is normal and will not affect the actual adjustment.
With the presser foot adjusted all the way down, rotate the gear clockwise and bring the presser foot back up. Count the clicks of the gear. Raise the presser foot two clicks back up. Again, you most likely will not see the presser foot move.
With the presser foot two clicks up from the bottom, your machine is adjusted and you are ready to trace the design and sew it out.