Allow an old fart to reminisce...
I started investing in '92, at the height of the recession caused when Reganomics finally went bust. And while I wasn't investing at the time, I was nearly an adult when black Monday happened in '87, so I remember the impact well. I also remember my parents waiting in the gas lines in the 70's and the endless carpools, and the belt tightening from those years.
I've invested through '92, the dot com bust, the 2001 bust, 2008, 2020, and now this. Plus a whole lot of random market farts along the way. I was pursuing FIRE before it had a cool name. I read Your Money or Your Life in '92 or '93 and decided then and there that I would not work my whole life. I was also a devotee of the Tightwad Gazette. Good times...
Anyway, when I started investing, it was such a joy to watch my money disappear into a block hole. /s. But I kept at it. And every time the market turned around, I saw the miracle that happens. All those shares I bought when the market was crashing were still there, only now they acted as a big inflatable cushion, pushing my money higher and higher. And, sure, the cushion developed leaks over the years through various crashes, but I kept going. And going. I built a machine that works and I trust it.
Bought a house in '96 when interest rates were north of 8%, and prices were rising because we were in a fast growing area. We weren't sure if it was a good decision, if there would be a crash, etc. It was risky, but we needed a house and weren't interested in timing the market. We just bought what we could afford and left it at that.
I never stopped contributing, never changed my allocations based on fear, and never took out a loan or withdrawal. I became lean-fire in 2005 (and my max income to that point had not topped 60K), but kept working because things weren't too terrible at work. I finally decided to pack it in for good in 2012, but developed some side hustles (not from need, but desire) that happened to pay some money. So I kept investing. Still do.
And I think my biggest tip is this: Don't worry too much in the early years. I think it was fortunate that when I began investing there was no internet so you couldn't look every day. Even learning what the stock market was doing meant reading the morning paper or watching the nightly news. You had to wait for your quarterly statement to come in the mail from the brokerage to know how you were doing. That, I believe, made it much easier to train myself not to worry about it. The deluge of information we have these days is not always helpful. Back then was literally the definition of set it and forget it.
Through every downturn there have been screams of doom, and that this time is different, and that everything is imploding. And I don't deny that the US and world are at a concerning point. I wake up every day and carefully open one eye to see if the world is still standing! However, I also know that if this time really is different and the US truly goes down the drain, my investments will be the least of my problems. I can't worry about that. I can only control what I can control. And that has always been to stay the course, invest according to my risk tolerance, and live a frugal and sensible life. And vote. Anything beyond that I cannot fix, so I try not to worry.
What I'm saying is that, so far, making a plan and staying the course has worked. Will it work forever? I have no idea, but I also have no real, concrete reason to expect that it won't. Hopefully this helps a bit.