diet changes.. HELP

Hey ladies!! AF due around 4/5.. looking for any diet changes that you've made to help get pregnant? Or any changes at all that you think helped! I started taking preg prep vitamins because the reviews were pretty good.. but I am a huge Mountain Dew drinker! Trying my best to cut back this month.. just curious if anyone has any suggestions on anything else to do to try to get pregnant! TTC for about 6 months now..