I do not consciously look for a subject in particular, and just let it happen. That way, I end up with something I feel is amazing and surprising; subjects that awaken my creative instincts, and sometimes I find in unusual places.
For example, when traveling in the underground (subway), the sight of people of different sex, age, and races holding on to the same grab bar becomes a subject of my painting or the sight of footprints or tire marks on a beach. While traveling, I am always looking out for inspiration, and recently, I converted views from airplane windows into my paintings.