Stem cells maintenance is the name of the game
Every time you attempt a fast, it gets easier as Getback noted. Half of it is just psychological and habit. Make a deal with your self ahead of time. Just give yourself permission that if you truly start to feel bad (persistent nausea or dizziness, or bad headache), then just stop this time and try again another time. Every attempt gets your body more used to it. It's not a test of your manliness.
Here is the advice I'd give based on my fasting experience:
1. First get fat-adapted. If will make it soooo much less painful (assuming you have some body fat..for most Americans, that is not a problem). Low carb or keto or Carnivore. Whatever works for you. I'd say get fat-adapted for at least a month before trying fasting. It is not required, but it will be a lot less stress and pain.
2. Hunger doesn't increase forever. It comes in waves. It increases, but then subsides again. It is controlled by the spike release of the hormone ghrelin base on your past eating patterns. It's just reminder "Hey, it's that time of day we usually eat. Don't forget." After a while that hormone release fades until the next normal eating window and then you will get another wave. Understanding that it is an impermanent sensation that won't just keep increasing and increasing and don't be afraid of it, is half the battle. Don't panic when you feel the sensation. Ever go to bed kinda hungry but wake in the morning and not be hungry anymore?
3. stay busy.
4. Stay hydrated.
5. Supplement electrolytes and micro nutrients if you want.
6. Black coffee or green teas are fine. Nothing with milk or sugar obviously.
7. Arrange your fasting window so that as much of it occurs while you sleep as possible. That's why the 24 hr fast is not so bad. 1/3 of that window is spent asleep.
8. On a longer fast or first time, careful how you re-enter feeding. On a longer fast, there are some risks if you just go hog wild immediately after the fast. With a 24 hour fast there is little danger but why risk it. See "Refeeding syndrome". When I was first starting out after a fast I'd start with a big cup of bone broth and then wait an hour or two, then have an egg or something not too crazy. Wait a couple of hours and then resume your normal schedule.
9. Listen to your body. A little hunger is normal. If you really feel crappy, don't try and muscle through it. Just stop and try again in two week.
10. After any fast longer than 24 hours, its best to wait at least two week before trying another. Remember the pump. The refeed is as important as the fast to get the full effects. A good healthy refeed is what signals the body it is safe to start producing stem cells and begin recovery.
I'm not a doctor, but that's how I do it. If you got serious health issue, consult a doctor first. If you are taking medications especially like anything that effects glucose, BP, talk to a doctor first. In general it's probably a good a idea get a check up first and tell them what you plan and see if they have a real reason why that would be risky for your situation.
$0.02