• Eat more fibre. (Check nutritional information on packets or go for wholegrains/fruit/veg.)
• Eat less sugar. (Reduce refined sugars – try to limit yourself to less than 20g refined sugars a day. Feel free to eat what fructose and lactose you want.)
• Eat more protein. (I am vegetarian and wasn’t getting enough. Might not be the case for carnivores.)
• Don’t starve yourself of fat/non-sugar carbs.
• Fast for at least 12 hours everyday. (Eg. Between 8pm and 8am.)
• Make breakfast your biggest meal of the day. (Provides energy when you need it the most.)
• Eat more resistant starch. (Wholemeal bread instead of white bread, wholemeal pasta instead of white pasta, brown rice instead of white rice, etc.)
• Drink more water/sugar free drinks.
• Exercise. (CouchTo5k, walking, swimming, cycling, anything that isn’t sitting down all day.)
• One (or more) day a week not thinking about any of the advice above.

Disclaimer: this guide isn’t gospel, it is 100% anecdotal, but it has worked for me.