long post

count calories, period （⌒∇⌒ゞ）
don't be hyper-anal about the specific numbers, just give yourself enough of a gap that you don't need to think too hard about it
for my current diet, my caloric goal is 1600-1800 a day, I think I burn like 2200 on a fairly typical day and maybe 2000 on a totally idle day
I'm a pretty normal guy with a job that isn't sedentary and has me on my feet

to stay in my goal, I eat two meals a day, breakfast and dinner
some days, I might end up below 1600, some days I might have ended up a bit above 1800, but I have enough of a gap between that and how many calories I expect to burn by existing that I don't give a shit about the specifics ヽ(´∇`)ノ

very important note:
how much muscle you have is the biggest factor in how many calories you burn daily above all else, and thus building muscle is the one real goal if you're exercising for weight loss reasons (or be able to eat a lot without it mattering as much)
your body is very efficient and so a very strenuous day might still only be 400-500 calories off from a lazy day lol - which is a fair bit, but you will also just be hungrier lol

if you don't think you have much muscle, you might only be burning like 1600 a day in the first place and thus you you would need to exercise if you don't want to eat tiny portions

you want to regularly eat something with like meat or nuts or whatever because lol protein, you don't want to lose muscle (・∀・)
this isn't particularly hard though, most people eat a sufficient amount of meat, the current protein craze is insane

two 800 calorie meals a day would be pretty filling, that's like a decent burger and a drink twice a day if you're particularly unconcerned about being on a diet and don't care about the other health effects of eating like that (but cut the fries, they're obnoxiously calorie dense and you'll add like 400 calories to your meal out of nowhere)
fruit is great to snack on too (a big-ass apple is like 110 calories lol), just don't go nuts since you're still counting; you might feel a bit peckish and thus eat an apple or a peach or some shit
really, one of most large fruit is like 100 calories give or take

any snacks in a bag are probably going to be most of a full meal's worth if not more (eg, potato chips, even a snack sized bag; I've seen shit where the serving size was unreasonably small vs the amount in the bag so you could eat like 600 calories in one go without thinking about it) (;ﾟДﾟ)

remove sweetened drinks (maybe limit to one a day and water/unsweet tea the rest), dropping sweetened drinks makes your job a LOT easier since you don't just add like 250 calories to every meal out of nowhere and thus have leeway for something else
again, count calories, round up if you're uncertain, and if you really don't know how much you ate after a meal (eg, you went out to eat with family), assume it's at least 800 or so

if you're not already somewhat active, make sure you do at least a little bit of strenuous activity so your body isn't losing muscle (not even much, just enough so your body knows that it still needs that muscle mass lol)
remember, since muscle mass is such a big deal in how much you burn every day, your body is fairly ready to discard it

you can give yourself a "cheat" day with a higher caloric limit if you expect to hang out with friends, as long as you still count and only do it like once a week (maybe you'd be fine with 2100 that day, which would get you 3 700 cal meals, or one big-ass meal and a normal one), I do this (´人｀)

and lastly, stick to it (＾Д^)
it might be a bit hard at times, but it's effective
if you don't need to drop the pounds fast, just cutting out sweet drinks might put you under your daily calorie load without any other changes and thus you would still be losing weight (just not quickly) if you're not already quickly gaining weight


tl;dr:
how many calories do you burn in a typical day? eat less than that
if you don't know and you're an ordinary guy, it might be like 2000, so eat less than that many, ez ヽ(´ー｀)ノ