A useful resource that has projects, tutorials, and other helpful tips for working with the Bernina embroidery machine is the Bernina Blog, We All Sew.
This blog post from We All Sew goes over things to consider when adding embroidery to garments, whether that's adding embroidery to something before it's sewn together or a ready-made item of clothing.
Embroidery Machine Troubleshooting and Common Issues
This is a great video that goes over a lot of common issues that can happen when using an embroidery machine, you can easily skip around in the video to go to specific topics to find the solution you may need.
