The next step is one you may logically deduce. You will now calorie count 3 days a week, but at the increased count of 1500 calories per day. For reference, note that a person of normal weight for his or her height and body type can lose one pound a week on average at a calorie count of 1500 a day. It takes a deficit of 3500 calories to lose a pound. With an average of 2000 calories per day to maintain a healthy weight for a person who is normally active (not working out or exercising especially, but also not a couch potato), a 500 calorie deficit for a week will result in an average loss of a pound. Of course, age and height will also play a part in the rate of loss, but most people should be losing weight at 1500 calories per day.
That being said, a person who is overweight will lose more weight as maintaining a heavy body requires more calories. As you lose more weight, you will lose more slowly unless you increase activity or decrease calories more. I don’t recommend reducing the calories too far though as it is harder on your body and often does not yield results equivalent to your added sacrifice. My future plan is to increase activity and hold on the calories at 1500 or so once I reach a lower weight (likely once I reach 200 lbs.).
At this point, you may also start to think about the effect that certain foods have on your hunger levels. That is, do you feel hungrier after eating an apple? Do you feel hungrier after eating bread? One of the things we don't easily realize when we eat as much as we want and whatever we want is what types of foods are stimulating our appetites. When you start to count calories and control the food you eat more purposefully, you can get a feel for the foods which make you hungrier rather than sate you.
For me, eating an apple will almost always set off extreme hunger. This means that an apple is a poor choice of snack for me, but it is okay to eat one paired with other parts of a meal as the overall mix of protein, fat, and carbohydrates will not have the same effect as a lone apple. Try to think about how to have your favorite foods paired with others so that you aren't making yourself hungrier needlessly by setting off a spike in blood sugar and a subsequent crash. Contrary to what some people believe, many healthy or seemingly healthy foods can cause the same sort of blood sugar problems as sweets or refined carbohydrates. You don't have to give up any food, but just consider when you eat it and pairing it with other foods to mitigate the hunger-inducing effects.
As with the other stages, you may remain in this one as long as you need to in order to grow comfortable with this new level. You will know when you are "ready" to move on to more restrictiveness. Again, there is no hurry.