1. Yarn. Lots and lots and lots of yarn. Not just wool, but bamboo, cotton, soya.
2. Storage for number 1. Clean dry and moth proof. Also child proof and invisible to non knitters who cannot possible understand the need to have so much surplus yarn.
3. Courage to frog if necessary and to try new things.
4. Patience to know that every thing can be undone and that even mistakes teach us something about ourselves or our knitting. Throwing knitting while momentarily satisfying is bound to result in tears.
5. Time awareness. Always remember that time goes twice as fast as soon as you set a deadline so if possible avoid saying when you'll be finished with a project. or knit twice as fast. Giving up eating and sleeping could buy you some extra hours but may have other side effects.
6. Acceptance. If you don't want to spend time swatching then accept that at least some of the time you're going to end up with a garment the wrong size or shape. If you can love the process and accept the result all good.
7. Have fun. Sometimes we forget that we love knitting, especially when the pattern's wrong and we rip it out three times.
8. Gift your knitting to those who will love it. Anyone who is likely to boil your garment might be better off with a good book. One that tells them how to care for woollen garments.
9. Let go of your knitting. Once you have gifted your knitting to someone worthy you are no longer in control of what happens to it. Even if they boil it. See 8 and learn.
10. Be proud of your skill and the result. Wear garments with pride and knit in public because it's not illegal or anti-social. Unless you use your knitting needles to stab the next person who comments 'OH you're knitting" inthe same tone of voice that implies they've just trodden in something unmentionalbe. See 4.