I have around 1500 calories each day, but I try not to get too obsessed by it.
I try to stay under 250 calories for my breakfast, 350 for lunch and 500 for tea, which leaves a bit of room for snacks/treats. The meals I buy/cook routinely are all within these allowances so I don't have to think too hard about it.
I just have to re-think/re-adjust when something out of the ordinary comes along, like meals out, or if I decide to treat myself to something a bit more indulgent.