Not CFS, but I have cancer and am on long term treatment that causes fatigue, so not the same but the same result really (plus mine might kill me).
I plan in rest and I force myself to have a lie down even if I think I’m not that tired. So my days, our holidays, whatever are planned around the time I’ll most likely need to nap. Like a toddler’s would be.
I also go to bed early. 8:30/9pm I’m heading upstairs to bed with my youngest. I don’t go to sleep then, but I do at least lie down.
And on the flip side of that, exercise. I get 10,000 steps a day most days. I also hike and swim and lift weights. May be more tricky if you have any joint or muscle pain. I don’t at the moment, but have in the past, and I’m so grateful not to be in pain right now, so I absolutely make the most of it. My approach is to use it or lose it. If I truly don’t feel well, then I don’t. But if I do, yes, I’ll walk 5 miles. I keep very intentionally active to the limits of what I can do.
I also have a very involved and supportive Dh. I am not working at the moment, so from my perspective, I need to do the stuff that supports him being able to keep us afloat, if I can. I do most of the school runs, the cooking, a lot of cleaning, but anything I can’t do, he is there 100% doing it so I can look after myself.