Non-Violent Communication ("NVC") by Marshall Rosenberg changed how I communicate forever. The big lesson to focus on people's underlying needs in a conversation = gamechanger.
Weigh the ROI of changing your environment vs changing yourself
A lot of people on HN are do-it-yourself, bootstrap types. So you'll naturally get "why don't you just do XYZ."
There's merit in that, but sometimes changing the environment is more effective. That environment may be literal physical location (closer to friends or activities you're interested in), a job environment (different industry) or, at a smaller scale, your home environment. I finally started updating my place and having friends over and it's made a huge difference.
On a personal note: a hard lesson I had to learn for myself is that having fun (as weird as it sounds) is my responsibility. I found that I tended to look "outwards" for stimulation, fun, validation...waiting for the world to give me things.
Hanging out with people who were great at cultivating their own fun & energy helped me realize 1) this is something I could cultivate and 2) I was shirking responsibility.
IMO this cultivation of one's own energy is a long, internal journey. But worth it.
I am having a similar problem as OP (in my 30s now but yearn for the social environment of 20 somethings) and am debating digital nomading a bit to change my environment, as where I live seems to pose a lot of psychological inertia since I spent most of my life here and fall into the same patterns - everything seems like I've "been there and done that". The idea of weighing the ROI and being responsible for my own fun is a much needed reminder so thank you for this comment, I really needed it.
Many responses here don't address OP's question about day-to-day practices.
My spiritual practice: meditation, journaling, breathwork. Occasionally, psychedelics with close friends in nature, which often starts out with a prompt regarding with we want to get out of the experience
Just want to say I think your response is well articulated, and has been sitting with me for days. Reflecting on how "schedule first" is driving things in my org...
I write about new age trends like ecstatic dance, psychedelics and more. I do my best to give a balanced view - talking about the origins and potential applications - and not just calling everything BS.
If you're a curious skeptic, you'd like my newsletter:
Philip Morgan specifically has a ton of advice in the area of positioning oneself to be a sought-after consultant in technical fields. Even if I'm in UX and content I found his book "The Positioning Manual for Technical Firms" to be invaluable:
Third this. Perhaps the most organized, complete set of free info on consulting, pricing, and negotiation. His book Double Your Freelance Rate is pretty great too.
Ask and ye shall receive...self promos! My blog is a smattering of personal development and increasingly more about content strategy as I try to find a niche.