We present optimizations of corrugated metallic sheets for desired electromagnetic responses. Patches of finite extents are considered and deformed to achieve the required characteristics. Optimizations are performed by using genetic algorithms (GAs), while the required accurate solutions are performed via the multilevel fast multipole algorithm. In addition to improvements in GAs, the optimization environment is enhanced by using dynamic accuracy control and adaptive mesh refinement to handle thousands of critical simulations per optimization. Numerical examples involving corrugated sheets that provide focusing abilities at desired locations are presented to demonstrate the capabilities of the developed optimization mechanism.