This is one of many, many things I teach in the Remove Your Covers workshop - what happens when your bobbin refuses to wind easily. Many machines don't have an adjustment point to fix this issue, so in that case, you have to do what you have to do.
All you need to do is wind your bobbin as usual, which the thread should move itself up and down the bobbin for a nice, smooth wound bobbin. But if your bobbin winds top heavy, bottom heavy, or middle heavy, you'll have to help guide the thread manually with your finger.
Here's a short clip demonstrating how to do this.
