|I sew most of my buttons on by machine, which is a real time saver. This technique will work for most buttons with holes (no shank buttons). Some sewing machine manuals will explain this technique, but I'm not sure how many sewers do this.
First, drop the feed teeth on your machine. If the feed teeth do not drop, your machine should have a small plate to cover them.
I use a piece of scotch tape to secure each button to the garment.
Some machines come with a foot to hold the button down. On my machine I remove the foot, and just position the button under the pressure foot shank.
Select a zig-zag stitch (some computerized machines have a button setting). Test your stitch by turning the flywheel by hand to make sure that the needle will hit both holes.--This is a very important step so that you don't have a broken needle or button or an out-of-time machine. As soon as you are sure that your needle will clear both holes, complete the stitch by machine.
Readjust the button for additional holes. Retest the stitch each time you readjust the button,to be sure the needle will hit the hole. I usually wait to clip threads until all buttons have been stitched.
For a little extra security, you can add a little seam sealant to the back side of the stitching. I have found this application very secure, even without the seam sealant.
Remove the scotch tape after all the stitching has been completed. Also remember to put your feed teeth back. (On many machines, the feed teeth do not return to position until after you have taken a stitch).
I think that my machine does a prettier job of attatching buttons than I can do by hand. Now if it could only do those shank buttons...