In a nutshell & off top of my head, the idea is to prevent the pancreas overproducing insulin in response to a flood of sugar, which can result in too low a level of blood sugar a while later & all the horrible symptoms that come with it: faintness, drowsiness, anxiety, dizziness, nausea, sweating, flushing, palpitations, shaking, inexplicable irritability . . . So . . .
Complex carbs with a good portion of protein at every main meal.
No white carbs, no sugar (sorry).
Fresh fruit is OK but not too much in one go & be careful with high sugar fruits such as mango.
Dried fruit if you must but only in small portions & with nuts or another source of protein.
Have any fruit salads with a main meal & high protein natural yoghurt (such as Greek).
Plenty of veg - fibre slows down digestion & gives meals more staying power.
Eat spuds with skins & avoid massive baked spuds or big portions of pasta/rice! Again, always have with protein.
Sweet potatoes better than white & can help cravings for less healthy sweet foods if you miss them.
Moderate sized meals rather than big/small.
Try not to go more than 4 hours without food.
Healthy snacks between meals if you need them - eg oatcakes with a little (cottage) cheese, natural yoghurt with nuts, no added sugar muesli etc.
Check labels to be sure carb content is not too high - e.g. muesli that contains dried fruit can be surprisingly high in sugars.
No undiluted fruit juice & if you must have juice, have it with a main meal.
Alcohol upsets blood sugar (sorry - don't shoot the messenger!)
Be wary of caffeine too.
Never exercise on empty. Have a healthy snack an hour beforehand.
A little supper, such as a small bowl of muesli or couple of oatcakes with natural yoghurt before bed can help get you through the night.
End of sermon!! Just kidding - all things that helped me - may not suit others, but maybe something useful to take from it.
Wx