21:30 For books you sell directly from your website (e.g. not via a retailer like Amazon), you can use a custom dedication for each sale. Write the dedication in the book ("To Ali, the coolest guy I ever met"). Record a dedication for an audio book. This bit of personalization is the extra touch you can give to the products you sell.
32:00 Do not quote others by default. When you're producing content, limit yourself to the essence. Do keep the quotes/source, though. Only when people ask you about it, give the extra content (which you can do, because you've kept this information as well).
35:00 You're often tied to the identity that you got because you studied something. For example, if you studied Computer Science, you're tied to the identity of developer. Especially if that's how you've started to profile yourself on the web. But to yourself you could think: "is this really what I want to do in the long term, or am I just tied to the identity of it?". A bit similar to "a life divided in boxes", as noted in Building A Second Brain, Deep Dive with Tiago Forte.
36:00 Continuing on the last point, a way to figure this out is to ask yourself: "What do I hate not doing". You could aim for a Portfolio career: do X on Monday to Wednesday, then Y on Thursday and Z on Friday. Doing all those things could even lead to a realization that either X, Y or Z is what you actually want to do. Trying more things at least raises the chances of finding you "why".
38:00 Music theory is like language grammar. People speak languages without thinking too much about correct grammar. They just listen and speak correctly by doing it a lot. In the end, music theory is just a formal way of talking about music, but absolutely not necessary to learn. It's better to make up your own system of writing music, inspired by what music you like. Learn from interest (Just in Time) instead of by the book (Just in Case). Also see Just In Time versus Just In Case.
01:26:00 Turn random email connections into in-person connections. Take note on who you email with. Then when you go to a city you've never been to, check your email connections, find people nearby and offer to meet up. It might take a lot of time to do this email management and emailing back everyone who emails you, but it might be worth it in the end.