1. Use as much natural light in the pictures as you can. Move your dish towards the window or even take it outside. It is important to plan ahead. Let's say if you are cooking dinner at 7pm and the sunset is at 6pm, most likely you won't be able to take a good picture. If the light is bad, better not to take the picture! it won't look good and appetising. Unfortunately this is the truth.
2. Try different angles. Sometimes I have to stand on the chair, or lie down on the ground. Move around your plate: try to shoot from different angles. Once you upload the picture to your computer, you would feel which angle is working the best.
3. Style your food but remember the less is better. Don't put too many props around. Some simple fork and napkin might work just fine.
4. Take a bite! If you are cooking a pie or a cake, photograph it first when it's out of the oven. After you took a few pictures, take a bite or slice a piece off. The photograph would look like the food is in the process of being eaten and create a certain vibe.
5. Do your research. Look for images and blogs which inspire you. Don't be afraid to copy the image. It is a good tool to learn. Your photo would never be the same as others! We are all individuals and bring our own vision to the picture.
Cook. Experiment. Enjoy.