I find making a good Chinese style fried rice both simple and difficult at the same time. It is simple in concept but difficult in practice. I also like to differentiate between a home style as well as a restaurant style fried rice. I do believe there is a difference.
Home style fried rice, this is the common recipe of day old rice and then whatever ingredients you have to add flavor and texture to the dish. Rice here makes a difference as the Chinese and Thais tend to use "long grain" rice. While Japanese and Koreans like the medium to short grain rice. I find that long grain rice works best for fried rice or "chao fan". Less sticking and clumping with the long grain.
Restaurant fried rice, uses freshly cooked rice, that has been cooked with slightly less water so make it less sticky. Can you imagine a restaurant wasting space with day old rice specifically for making fried rice? And let's face it, most people are taking about the fried rice at their favorite Chinese restaurant, right?
Anyways the keys are really the wok and high heat. These two things are the keys to making a good fried rice or just good Chinese restaurant food. A well seasoned wok will allow you to toss the rice easily so as to make for even browning. The high heat will allow you to brown it without drying it out. You could make this in a flat pan but it is a bit more messy and for me not as fun. Another secret for the home cook is adding beaten eggs to the rice, this gives them a coating to prevent drying and sticky clumpy rice. We don't have as much fire power as a professional chinese kitchen.
As with all good cooking technique, have your ingredients prepped and ready to go before you even think about cooking them. In this case have your rice ready, add enough beaten eggs to coat all the rice, mix it well till all the grains look yellow. If you are adding some kind of meat, this is the time you would half cook it first in the wok. Wash out your wok and then prepare to cook the rice. Raw vegetables can be cooked with the rice later or precooked with the meat.
In a hot wok, add some oil and swirl it around the wok till it covers the wok, then toss this oil out, and add fresh oil. Wait just a second or two, then add the rice to the wok and spread it out over the sides for just a second or two. This allows the rice to get it's initial browning. The hotter the wok the less time it takes, the less hot the more time.
After initial browning, it's time to toss the rice, this is where the wok outshines any other pan. Moving food in a wok is very easy as the sloped sides naturally allow the food to come back to the center, you don't have to chase the food. If you coated all the rice grains then they will not stick to each other, they will slide around easily. If they do start to stick, add just a few drops of oil around the edges of the wok and let them slide to the center of the wok.
When you can smell the delicious aroma of rice then you can start to add whatever ingredients you want. Some of the meat and vegetables and some extra beaten eggs if you want. At the very end of cooking time, is when you add the wet ingredients, this will keep your rice moist and soft. Soy sauce (dark or light or both), oyster sauce, and or sesame oil. When you add the wet stuff, drizzle it along the edges of the wok and let it slide to the center. This adds a bit of steam and also doesn't reduce the heat too quickly. Heat is your friend in wok cooking. A few more tosses and you are done.
For a visual demonstration just go to Youtube.com and type in "cha han", "chao fan" or just plain old "fried rice"