One of the hardest things about writing is keeping up a supply of snacks to munch on while you are going.
Writing uses brainpower, and your brain requires calories, particularly glucose.
So, you need snacks.
Then you need to pace yourself for continuous grazing in a way that you don’t just get fat, sitting on your ass. And in a way that doesn’t just eat up all of your money as you go.
I recommend chocolate. Cheese. Coffee. Tea.
Reward yourself with alcohol if you must, but I tend to not imbibe when I work, because the mind is a pencil, and works better when it is sharp.
That is all.