Two Tips After 602 Hours of Learning Icon Design 1. Replicate icons from the most commonly used libraries. Focus on replicating icons at one size, like 24px. While there is no easy solution for achieving optical balance, you can train your eye by replicating good icon designs. 2. You may not understand the reasons behind many design decisions at first, but most icon design blogs and advice will become clearer after you spend 200 hours replicating icons.