Advice "to my former self" from my 30th year. The worst year of my life - but also the best because of the lessons it taught me. If I had to live it over again, here's what I'd wish I had known.

1. Books, techniques etc. only help if you're solving the right problem.

2. Identifying the right problem is difficult - and painful. It requires honest introspection. You have to dig deep inside and go into some pretty dark corners.

3. You can't make incremental changes towards a new mindset. You have to pull yourself out of your set patterns of thinking. One way to do this is to set completely different constraints. For example, if you're trying to be more efficient at a task, it's not enough to change your estimates from 12 months to 11 (because you can fake/slog your way to it). Real change in thinking happens when the constraints are impossible under current assumptions (e.g. changing from 12 months to 3) - you HAVE to do something very different.

4. Habits take a long time to form, and regressing is easy. Keep things simple to avoid regressing.

5. Energy management is key to deliberate practice. Sleep well. Exercise.

6. If you can't bring 100% to the moment, the problem began a long time ago - e.g. maybe you didn't manage your time well yesterday and slept badly, or maybe you overcommitted your time, or whatever.

7. Your surface goals satisfy the ego. Your true motivations satisfy the soul.

8. Early success often sows the seeds for failure. "If you're not failing you're not learning."

9. Correct mistakes quickly and don't repeat them. Fail often, but fail forward.

10. Be present. Pay attention to the moment. Listen and pay attention to the people you're with - like you'd do with your child. Anticipate without solving. Help without trying to be the hero (or a crutch).

11. The ego will get in your way. Do something that you're bad at - regularly - to crack the ego. I picked Jiu Jitsu (not my own idea, my boss' - and it took me 6 months to warm up to it and appreciate what it's teaching me)

12. Say "no" when you're not 100% sure.