Start hacking yet always look for and apply (most current) best practices along the way as much as you can or where applicable. Constant refactoring your old co

Start hacking yet always look for and apply (most current) best practices along the way as much as you can or where applicable. Constant refactoring your old code and learn functional programming (in addition to the classic imperative style). For Objective-C, master stuff like Block, Category (can be evil but very neat when applied properly), GCD, KVO, and ARC (as well as autorelease pool).