Yes, we can. Preparation is the conscious attack on a problem. It involves mulling the problem over, viewing it from multiple perspectives, discussing it with others, reading about it and daydreaming. We have complete control over this phase. Its success depends upon willingness and concentrated effort.
Incubation is the subconscious mind at work.
It is not subject to the will. The subconscious does the real creative work, though it depends almost entirely on the conscious preparation that precedes it. Illumination is the sudden flash of inspiration. It surprises us. It astonishes us.