Many years ago, I bought a preprinted panel that had outline stitches printed in white around the designs and I practiced hand quilting on those, making sure I stayed on the dashes and left the spaces free. That helped me stay straight and have even stitches, even though the dashes that were marked were fairly large for hand quilting. With practice, I've gotten my stitches smaller. For marking, try a Herra marker. It is a plastic flat curved thing that fits nicely in your hand with a sharp edge for marking. When you run this along a ruler, or in a stencil, or even a free hand design, it leaves a crease in the fabric that is easy to follow with your needle and thread and there's no mark to wash out and it's not messy like chalk. I love it! Also, I always quilted with a hoop until a few years ago. While sitting in my chair watching tv, the hoop got in the way of my view, so I took the hoop off. Wow... I found it so much easier to quilt without a hoop and I've not used one since. A good tip to remember is try to put your needle as straight up and down as you can when taking a stitch. When repeated, it kinda sets up a rocking motion and helps to keep your stitches smaller than when the needle goes in at an angle. Keep practicing. What seems difficult now will very shortly prove to be easy and it's so rewarding!