For me, I just try to lessen the things I eat that may have too much fat, salt, carbs, etc depending on your target.
This will work on a basic level only, but it is easier to manage and follow.
If you suddenly change your diet, most likely after a few weeks or months. You will just go back to your usual, because your body did not have sufficient time to adapt to your sudden diet change. The most important thing in diet is consistency, and it will take time for the results to show.
And don't forget to exercise regularly