I go in waves where I pay more attention to one thing for a while, but I'm usually low-to-medium maintenance.
I have a quick 3-minute makeup routine in the morning. Foundation, coverup, Benefit Georgia (pressed powder that just makes my face look a little glowier), a little blush, some very light mascara, and lip color. I'm not sure any of it makes a huge difference and it's definitely a natural look, but it does make me feel more awake and polished. Of those, I think the three that make the biggest difference are probably the foundation, blush, and lip color, so those might be good places to start if you want to get into a regular makeup routine.
With hair, I probably should pay more attention, but I just hate the effort involved. To be honest, hairstyling just feels like the beauty equivalent of washing dishes by hand to me. A lot of tedious effort, and then you just need to do the same thing again anyway the next day.
In the past, I've put more effort into trying to make it look straight and sleek. But I started wearing it naturally curly a few years ago and really like how I can basically just wash, let air dry, and put a little product in and at least have it look like it's doing something, even if it's not really the most polished look in the world. And, frankly, messy curls probably suit me better than sleek, straight hair. Certainly better than in-between limp but frizzy hair, which was what it actually looked like most of the time. I probably should get cuts more regularly than I do. I try to go every 8 weeks, but it's sometimes much longer.
I usually paint my toenails in the summer. I generally use a quick-dry polish or topcoat so I don't have to wait for it to dry. Sally Hansen has a line of quick-dry polishes that I especially like because they have a flat brush, which gives me more control so it looks neater. I rarely paint my fingernails except for special occasions because I'm not a fan of not being able to touch anything (even quick-dry takes long enough to be annoying). Rarely do salon mani/pedis. They're nice, but I feel like it's hard to justify the cost, and I have limited patience for the small-talk-with-a-stranger part of beauty treatments anyway.