Don't eat sugar. If you can avoid eating processed man-made sugar (believe me, it is everywhere), you'll by necessity be avoiding so much of the bad stuff. Do that and ephion's tips, you'll be fine. Expect unbelievable difficulty when reducing carbs for the first two weeks, followed by a health, cognition and wakefullness spike, followed by normal life with a little bit more cognitive stability than beforehand.
This is a thread where people can ask questions that they would ordinarily feel embarrassed for not knowing the answer to. The previous "stupid" questions thread is at almost 500 questions in about a month, so I think it's time for a new one.
Also, I have a new "stupid" question.