Pam from Off the Cuff shows how to make a 2-piece shirt sleeve placket. She also includes a free pattern for the pieces. She makes these entirely at the machine, with only finger pressing during the construction. (She gives it a good pressing with an iron at the end.) Her tutorial is detailed and loaded with photos to show step-by-step what to do, though she assures that once you’ve got the process down it only takes about 5 minutes to make one. Go to Off the Cuff to get her tutorial.
[photo from Off the Cuff]