Make sure you have your bobbin in correctly. That the bobbin thread is feeding in the right direction.

Also that your top thread is fed correctly, make sure that your needle is at the highest position when you start to feed the top thread.

YouTube is a good place to look for visual tutorials if you're a read, look, do learner. Keep your manual next to you and search on YT.

Good luck, you'll catch the hang of it. I had to get my manual out after a four month break from my Isodore/Brother when I came back from the Mainland. lol We've all been there.

Ruby

PS Each machine is a bit different, but between your manual and a visual walk-through video you should get the picture.