Difficulty: Moderately Challenging
Step1
Decide if you can do it yourself or if you want to hire it done. Hiring is much more expensive, but ensures a quality product (including a warranty).
Step2
Decide on sythetic materials such as polypropylene or nylon turf vs. natural planted grass. Note that different climates, shade or exposure, etc. may dictate the type of grass options. The various synthetic materials have their pros and cons as well. Do a lot of research online before making your decision. Keep in mind that manufacturer sites want to sell their product so compare their info against opinions of actual buyers if possible.
Step3
Measure the space you have for the putting green. Then use the square foot measurements and any other requirements or limitations to get quotes and choose a contractor (try to get 3 bids to save money and get a quality professional) or shop for materials for you do-it-yourselfers.
Step4
Then the work begins. Prepare the area and subgrade based on the type of material you are installing and either let your contractor begin or get to work yourself.