Here are my top tips for beautiful buttonholes!
1. Interface the area where the buttonholes will go. This will strengthen the fabric and decrease the chances of holes.
2. Always test your buttonhole on some scrap fabric before starting on your actual fabric. The buttonhole will need to be approximately 0.3mm longer than the button. Does the button pass through?
3. Make sure you are familiar with the order that your machine completes an automatic buttonhole. Practice sewing a few on some scrap so you get a feel for the order.
4. Mark where the buttonhole will go. Where the machine starts stitching is the most important mark.
5. Add Fray Stoppa, Fray Check or something similar on the front and the back of the buttonhole before opening.
6. When it's dried you can open your buttonhole. My preference is a buttonhole cutter. You'll just need to make sure you have something underneath to protect your table. Carefully line up the buttonhole cutter.
Alternatively a sharp seam ripper works well too. With this method I like to place a pin perpendicular to the end of the buttonhole so you don't rip through beyond the buttonhole.
A finished buttonhole!