Do sit-ups or cruches! That's what I always do... Do lots, even until it hurts. Infact, when it starts hurting keep going! Think with all the hard work, the pain will be worth it! Also don't necessarily eat A LOT less, but don't eat complete shit. If you focus on eating healthier foods with very little fat in them, you will lose what fat you have.

Also keep in mind that the less you do eat, the more you fast and starve yourself, the less you will want to eat. Your stomach will shrink. Though fasting is NOT a good a way to build muscle and lose weight. I would NOT recommended fasting, just eating less and healthier. And when I say healthy I don't mean like carrots and lettuce and all of that shit you don't want to eat... There is lots of healthy foods that also don't taste horrible. Like yogurt, nuts, fruits... Maybe instead of like a lays or cheetos eat some tortilla chips and guacamole. Avadcado's have a lot of good fats (like the ones in walnuts and figs) and still taste pretty good too.

Idk that's what I've done for the past years and it works alright, I'd say.