6th Deadly Sin:
Using a linty or waxed/coated thread in your machine
Gunking up your machine with lint or waxed thread is a great way to want to proverbially throw your machine against the wall. If your machine has slubs and gobs of lint and tends to shed more than Whiskers the cat during spring, you’re going to have a bad time. Stop. Clean out your bobbin area and thread path.
Suggestion: use high-quality thread. In the thread world, you get what you pay for. The cheap, discount store cotton thread will be very fuzzy and not very strong. If you’re spending this much time and money on fabric, notions, and a machine, it’s worth it to pay for the good thread which holds your project together.