In which ways have you self-improved that made you feel bad for not having done it earlier?

Yoga Nidra is how I learned it. Essentially self directed hypnosis.

I used to live in a world of constant thinking/planning and worst case scenario stress/fear/anger/tension. I was physical and mental mess. I was never relaxed.

Being able to relax was an effect that came with using my 5 main muscles of movement [LW · GW] and working towards aligning my midline anatomy and balancing my body.

As I've regained my natural range of movement, releasing physical restrictions, my mind has become much calmer. I sleep better, I feel at ease. I'm more accepting, less controlling, and without the constant thoughts about what I should/need/must do. (I'd almost use the word happy).

Working with these main muscles was my "in" to understanding things that are meant to help with relaxation - yoga, tai chi etc. Starting with my 'Base-Line' pelvic floor and rectus abdominis muscles.

It's been a long slog (my body was wrecked) but well worth it if you're willing to look at some anatomy pictures, palpate the muscles on your body learn to connect with them.

Reducing stress and tension on the body = reduced stress and tension in the mind.

One of my housemates is currently working on increasing his typing speed. He thinks keybr is actually quite bad, and he's settled on just using TypeRacer a lot.

I'm a quite fast typer (~95wpm) and learned from Mavis Beacon as a kid. I thought it was pretty great software, but the only thing I had to compare it to was UltraKey (which was very obviously worse). 

First I used keybr but eventually switched to software that focuses on problem digrams rather than problem letters. I'm not sure what the name of it is now.

Bought a laptop with mechanical switches and a ergo sculpt for when I'm using my laptop stand.

If you haven't tried mechanical they're very cheap these days https://www.amazon.com/Mechanical-Keyboard-Switches-LED-Backlit-Gofreetech/dp/B07897PY96/ref=sr_1_13?dchild=1&keywords=low+profile+brown+mx&qid=1604968538&s=electronics&sr=1-13

Still strongly endorsed. 

Unfortunately I was sort thrown out of balance by covid. 

Before covid started my sleep was the best it had ever been; I'd fall asleep within 10 min of going to bed and feel really well rested after 9h in bed. However, when covid struck I started working very long and weird hours and violating the basic sleep hygiene rules of the program. So things got worse for a while. 

I've now returned to trying to redo it, without the help of the app. What I learnt from that is that it matters a lot do it very exactly. Sticking with high precision to the actual rules set up (strict bed and wake times, leaving bed after 15 min if you haven't fallen asleep, so as to condition yourself to quickly fall asleep). 

Swedish program called learningtosleep.se

I think they just do whatever the standard sleep cbt thing is (at least that's what they say).

I'm considering doing Tucker Peck's Drug Free Sleep, but haven't tried it yet.

Interview with Tucker on CBTi.

The last 2 points are "meta" to the previous ones. Essentially, I used to get three types of advice:

1) "just be yourself", probably given by people who genuinely enjoy sports and have good eating habits. "Don't think about it too much, simply do the sports you like" -- when the problem is that I don't like any. "Just eat a bit of everything you want, yes including sweets, as long as you keep it diverse enough" -- when it feels to me like exactly what I was already doing.

2) insisting that I study the science of nutrition and physiology deeply, because doing the wrong thing can have terrible consequences. Following a diet will damage your health if the diet is unbalanced. The wrong type of a sport will damage your joints. Health improvement is described as walking through a minefield, only different maps have the mines in different places (and if you put those maps on top of each other, turns out the mines can be anywhere). Instead of giving you actionable advice, these people will look at any actionable advice you already got and tell you that doing that will make things worse.

3) enthusiastic endorsement of the latest food or exercise fashion, when it seems obvious that the same person will recommend something completely different a few weeks later.

The good news is that one can actually find actionable advice, without having to study medicine for years, and yet the advice will not be completely arbitrary. It may be imperfect, sure, but it will improve things, for a reasonable cost.

If I could send the first 3 points to my former self, but other people would read them too, here is the reaction my former self would get from them:

1) "This sounds too difficult and weird. Strength training is so unnatural; just take a long walk regularly and do some sport for fun. Yeah, vegetables are obviously good, but so is everything else; there are vitamins also in bread, even in chocolate, and all of them are necessary. I bet the cooks in restaurants know about nutrition more than you, and they are not allowed to sell bad stuff. This is just some crazy fanaticism which would only make you suffer."

2) "Nah, that's just some pseudoscience. People study nutrition and physiology for years; I am pretty sure it is much more complicated than that. Following such simplistic advice will only hurt you. Why won't you read a textbook or two instead? There are also many interesting YouTube blogs about nutrition and exercise; you should watch some of them, but of course not follow them blindly; you need to watch many of them to get a sufficiently complex overview..."

3) "Ok, dude, this is stupid. Why don't you instead go vegan / paleo / whatever, and do crossfit / whatever? This is obviously the right thing to do; here is a book written by a guy whose life was completely changed by it. That advice, that's just a waste of time. The only reason you like it is because you are too lazy to do veganism / paleo / crossfit, just admit it."

So I have regrets about not having done the right thing, and even not having the mindset that would have allowed me to do the right thing if somehow magically I would get the right info.