Planning and Design. Have a plan. Find out where things are. Consider the view, the slope, the exposure and soils of the area. Take into account the existing vegetation, the topography of the site and the intended use.
Group plants with like water needs together.
Decide where things will be. Decide when things will be done. Most landscapes are best done in phases. When appropriate, soil amendments such as spaghum peat moss or compost can improve root development, water infiltration and retention. Improve the soil before planting and installing the irrigation system.