Use an online calculator to find out your calorie maintenance level and what you should aim for to lose weight or maintain your current weight.
Start counting your calories. Weigh your food and portions.It doesn't have to be perfect but keep track.
Buy smaller plates so your plate looks fuller.
Find foods that are filling but low in calories, so you can eat plenty of them. Cut out or substitute every day things that are calorie heavy - so stop cooking in loads of oil, for example.
Cook from scratch or at least start to prepare some meals for yourself. Find new ways to cook vegetables to change things up roasting broccoli instead of steaming, for example.
Drink more water. Drink if you feel hungry or with a meal.
Don't cut out everything you enjoy. If you like crisps or chocolate, allow yourself these things - but stick to your calorie limit.
Walk more. Walk every day, no matter the weather. Even if you start by just 20 minutes per evening, do this and then walk some more. You'd be surprised by how many miles you can walk in a week.
If you start to feel hungry or are picking at food when you know you shouldn't be, put on your shoes and head out the door.
Forget about fad diets, don't overdo your exercise at first, don't starve yourself. The changes you make have to work in your life. You might have to tweak your lifestyle to accommodate them, but be realistic. If you're not an early riser, don't plan to go for a walk at 6am, for example.
Be patient. Realise what results look like. Staying the same is a result in itself. Aim to not put weight on first and foremost.
It's a marathon, not a sprint. If you over-eat one day, accept it. Just don't let one day creep into two days, or a whole week.
Don't eat and watch TV, or your tablet. Don't eat while your doing something else, and don't do something else whilst you're eating.