Take one of the tubes you just sewed, and one of the circular pieces for the cylinder tops. Put the circle inside the tube, with the seam allowances on the outside of the tube, and line up the edge of one of the tabs with the edge of the tube. Pin the tab to the tube, and then go on to pin the next tab to the left. (P.S. Do you like my DIY magnetic pincushion? So do I!!! Click the link to see my tutorial and learn how to make your own!)
The top of the tabs can overlap, and that’s fine, they’re supposed to overlap some. But make sure that everything is smooth 1/2″ away from the edge, where you will be sewing.
You don’t want to take a huge bite with the pin, like the arrows in the picture are showing. Just pin the tab, because if you pin the circle too far down, you won’t be able to line up the edges of the circle all the way around the tube. Work your way counter-clockwise around the tube, pinning the next tab to the left until the whole circle is attached.
Sewing a curved seam isn’t too tricky, but if you are a beginning sewist then you may want to cut a few extra practice pieces out of your scrap felt. That way you can get the hang of it without worrying about messing up.
Place the cylinder under the presser foot, with the seam of the tube down so that you will sew over the seam first. (That’s because it’s easier to keep the tube’s seam allowances open if you sew over them first, instead of having the seam allowance flip over when you come around to them.) Now you can see why it’s better to pin the tabs to the left, because the tabs are overlapping in front of the needle so that you will sew over them smoothly, and not fight against them, like petting a cat backwards.
Sew all the way around, attaching the top of the cylinder to the tube. You will need to keep the heads of the pins on the highest edge of the cylinder out of the way of the sewing machine’s needle bar as you sew.
Clip and notch the seam allowances on all of the cylinders after you’ve sewn them, so that the curved edge will be smooth once you turn the cylinders right-side out. (You can see why you want to use a non-fraying fabric like a felt, or one that’s been stabilized with an interfacing. You don’t need to worry about your seam allowances being this narrow on a felt or similarly stable fabric.) Take a look at the picture to see how they should be trimmed.