Location, location, location. Sound familiar. Your outdoor kitchen should be protected from the elements, ideally. It is designed for entertaining so an existing patio or lanai is ideal, but be aware of overhead flammable materials and blocked views.
Utilities. A sink requires water supply and drain. Electricity is important for a refrigerator, blender, rotisserie and lighting. Our islands are pre wired just needing a supply.
Design. When planning your kitchen make sure you consider counter space between components for comfort and accessibility.
Construction. Think bugs and the elements. We live in Florida. The materials should stand up to all conditions and be non-flammable.