Here's the deal: take in fewer calories than you burn.
Two methods therefore, best in combination: eat less and exercise more.
There is no wiggling out of that principle.
You can eat lower caloric foods in the same quantity or eat high calorie foods in smaller quantities. You can do more intense activity when you do exercise or you can do lower intensity activity for longer and/or more often.
There is no trick about this. No magic formula.
Except – aha! – the same ideas that work for Discardia over time also can apply here. You don't have to change everything all at once, you just have to start changing things in the right direction more often than the wrong.
Running less of a caloric overflow than you do now is still better than no reduction at all. If you can't get yourself down to a caloric deficit right away, at least move in that direction.
Making sure you walk 6000 steps a day instead of 4000 is better than nothing. Aim for 10000, but don't give up if you don't get there right away.
(All this can be adapted for those who need to gain instead of lose weight, of course. Switching to a healthy high calorie substitute for something you currently eat regularly, for example. Or starting to work in higher fat accompaniments to your meals such as nuts, avocados, and cheeses could help tilt the scale the way you want to be heading.)