Instead, crank the air conditioning, put on a sweater, and try an indoorsy summer read from Lifehacker. Advertisement Ego Is the Enemy by Ryan Holiday The title says it all; our own ego is often ou. Jen Stark, a Los Angeles based artist, is inspired by plant growth, evolution, infinity, fractals, psychedelic imagery and sacred geometries. Jen took four of our classic shoes and customized them by adding a psychedelic…