One of the biggest obstacles to simplifying a painting subject is our tendency to view it as specific content right from the start. Thinking of the round, red and green shapes as apples makes us want to show the viewer that they are apples even before the first brushstroke is made. This puts strict limits on how we might begin to interpret the forms that are before us.
When you begin to study your subject, look for clues about when you need to be careful and where you can be casual. It is often the case, for example, that the darks in a scene are what give final definition to the subject matter. Seeing this in advance frees up your brushwork in the earlier stages of the painting. It is not necessary to make sure the viewer can tell what they're looking at when the lights and middle values go on the page if the next layer is going to make it clear. In the "blocking in' stage you can allow the separate objects to run together, knowing it will make as much sense as you want later on. The looseness of the early layers can remain visible to some extent, which is not unlike the way we perceive reality.
I find it helpful to forestall thinking of the subject matter by name. When I'm deciding what sort of strokes and washes to make, I ask questions about proportion and distribution of color and value (How much of the shape is light? Where are the blue strokes concentrated?). I look for patterns that will inform what kind of strokes I should make (Are the strokes diagonal? Vertical? Horizontal? Are they rounded and curving? Rectilinear?
The answers to this sort of question have nothing to do with content. They refer only to form. They are abstract in nature. Theoretically, you could paint your picture from start to finish without ever checking in to make sure you've "properly" described the subject. Screw the viewer. It's up to you.