When I was very young, my vision started getting a bit blurry. I went to an eye doctor who examined me and found that I had a slight astigmatism in one eye. The other eye was perfect. He went on to say that my right eye, which had the defect, was defaulting to the left eye and letting it do all the work so to speak. He said, "I can give you a prescription for eye glasses, but I think it would be better for you in the long run if we first try strengthening your right eye. He suggested that I wear an eye patch over my left (good) eye for several hours a day and let the right eye do all the work of focusing.
Sure enough, my vision improved very rapidly as my right eye stopped slacking off and its focusing muscles got stronger.
This may not work for everyone, but I thought it was worth sharing, just in case.
Step 1: All You Need
1 eye patch about $3 at Rite Aid. Or very likely you could make your own easily enough. (https://www.instructables.com/id/Creepy-Eyes-Prank/)
Step 2: Why Am I Bringing This Up All of a Sudden?
This happens to me from time to time (about every few years or so) that my vision will start to get blurry and this technique always fixes it. Recently my vision started getting blurry again, and sure enough, even though I am now an old fart, it still works! I wear the patch a few hours a day and my right eye is stepping up to the challenge and getting stronger. My vision is getting better again. I'm amazed it still works even though I am getting kind of old.
A few common sense precautions you probably already thought of: don't use the eye patch while driving or operating dangerous equipment.