Definately do not follow a keto diet or any type of high fat diet. This will not maximize effects of DNP and will leave you miserable and very dizzy.
A good diet would be isocaloric or even 50-60% of cals from carbs and about 30-45% cals from pro, rest from fats. Your success w/ DNP will not be so much w/ what kind of breakdown, but more w/ the total amount of cals consumed. (DNP is very easy on muscle tissue and pretty much will just burn fat)
Fruit is a good choice for carbs while on DNP because it will help restore liver glycogen (DNP depletes liver glycogen rapidly).
Also, i noticed while on DNP the high GI carbs tended to make the heat worse.