Earlier quoted context omitted.
You also don't need to eat that much less if you're at a stable weight. 10% less a day means you lose a pound every 1-2 weeks. In my experience people seem to not like it when you tell them, after they ask, that you lost weight simply by eating a bit less every day consistently for a year.
Trying currently to lose weight: the reason why I don't 'like' this answer is because I don't track my food intake closely enough to be able to know what removing 10% means. So I guess that the first step is write everything you eat in a way you can monitor it, to be able to reduce it by a small amount if necessary.. Any advice on how to do it?
Get a food scale and measure everything for a few days, storing the information in an app like Cronometer.