Reader1, congratulations on finishing your first quilting class and two tops. From your list, I'd say you have learned a whole lot in a short amount of time .
What would I add to the list?
1. Don't buy impulsively. Take time to really think through your fabric purchases and have an immediate project in mind. Believe it or not, 99% of the fabric we fall in love with --if we don't use it soon--we'll fall out of love with it. A stash will build fast enough, one project at a time. Stay in control of your fabric, don't let it control you.
2. Not every project has to be completed. I try to think in terms of learning or practice sessions. If I try a technique or block and hate it, I don't have to make a whole quilt just because I started. I learned that that method/block/whatever is just not enjoyable. Move along. Learn something new.
3. You will discover your style. Be content with it. You may love working with small pieces, or you may prefer bigger pieces, faster finishes. You may like the quick pace of machine binding, or the relaxation of hand binding. You might like flannel, minky, or sheets for backing. Or you may only like to work with regular cotton. Stick to your style Call it your style. Own it and don't apologize.
4. Buy the best you can afford.
5. Your quilting mojo will come and go. Don't worry when you temporarily lose your desire to quilt. It'll most likely come back with a change of weather, health (better health), new baby announcement, scenery, financial situation, perspective, etc.
6. Keep your machine clean. The bobbin area builds up lint fast, which is detrimental and can be quite costly to remedy if it messes up fine parts.
7. Have doubles of the small items you use all the time. They easily get lost in the mess--I mean fun--of creating. Seam rippers, snips and/or small scissors, pincushions, etc.
8. Quilters are generous people. By nature we love to give and share of our time, talent, resources, knowledge, for the benefit of others and the joy it brings us. I've never met a stingey quilter. "The givers are the havers." We always have more than we can keep or use, and it just feels good to bless others.