The biggest thing you can do for healthy eating is to cut your portion sizes (most people eat far more than they should!!).
Eat with no distractions and really focus on what you're eating - put a small amount of food out (you can always have seconds) and eat slowly then stop when you no longer feel hungry. There's a big difference between eating 'til you're full and eating 'til you're no longer hungry and it's really useful to focus on one!
I'd also say - make nothing off limits, but try to find healthier alternatives - if you fancy something sweet then see if fruit hits the spot, if you fancy chips - have oven baked rather than deep fried.
If you want to calorie count (works for some, not for others) there are loads of calculators online to work out your BMR (the amount of calories you use to just lie still - it varies based on age, weight, activity and gender) and if you want to lose weight eat between that number and the number you burn each day by being active. If you want to maintain weight eat that number plus the additional calories you burn. But if you don't want to focus on calories - just keep an eye on saturated fats and salt in foods as they're the killers.
Often "lighter" options aren't that much different to the full fat versions so don't be pulled in to pricey versions of things.
Also - bodies have the same mechanism for thirst as for hunger so often when you're hungry, you just need a drink so drink first, then snack if you're still hungry (but go for healthy snacks if you can).
I think it's important to make it a lifestyle change (as it seems you are) rather than a diet! You're more likely to get long term benefits (healthier heart, living longer etc.) if you make it easier on yourself by making lots of little changes rather than just trying to cut out *everything* and make it really difficult!
I'm sure I'll think of more but I'm sure you've already had some great suggestions too!
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