Yeah, this is my issue. After a long day of (sometimes pointless) software dev, strapping in for more is draining. So as a contrast, I design board games (not digital) as my hobby. It is very analog and tactile and so energizing partially from just being a nice change of pace.
Your advice to start small is spot on though. I would even say one of the best first things to do is start by making a game mod. You don't have to invent so much, you just get to enhance. You get to something playable much quicker and learn about all your false assumptions.
Fair warning, game mods can take over your life too. Though I'd agree they can be easier and often can build on the community of the game your modding.
Another risk with mods is the game owner can shut you down at any moment, if public. I'll probably never do another mod or reuse someone else's IP for anything beyond very small prototypes. There are just so many tools now that you shouldn't have to.
I've had good luck with using my best time/energy for hobby projects and what's left over goes to work. Of course, this assumes that your hobby project is more important to you than whatever might be achieved by putting your best energy/time toward your job, but I also think a lot of people over-index on "whatever might be achieved by putting their best energy/time toward their job".
Sure, but let me first say there are tons of great podcasts about board game design if you are just getting started. Ludology, Building the Game, Fun Problems, etc.
I have played lots of board games so I have a good mental model of different types and the components needed. When I get an idea for a theme or mechanism, I build it up mentally first. When it feels like it might be fun or interesting, Then I'll start making some crappy cards or tokens. Some people will just write on note cards but I like something that feels more real. So I'll make some mostly text based images from a template. If they are cards, I'll print on paper and cut them out, then use CCG (MtG) sleeves and cheap playing cards to sleeve my paper. This lets them be shuffle-able. For other components or boards, I'll print on card stock. If I need something heavier, I'll print on adhesive label paper and then stick that to foam board or cardboard. The next and most important step is play test it with anyone and everyone you can.
Glad to provide more information if you're interested.
Your advice to start small is spot on though. I would even say one of the best first things to do is start by making a game mod. You don't have to invent so much, you just get to enhance. You get to something playable much quicker and learn about all your false assumptions.