A ceiling-mounted rain showerhead is more complicated to install than other showerheads. Yet, some of them do come with easy installation kits and guides. Some might need more work than others based on the size and weight of showerheads. The heavier versions need more reinforcement. For such plumbing jobs, it is best to call in a professional to help with the fitting.  Most showerheads will have a shower neck fitted into your ceiling, connected to the pipes. Plumber tape is used to seal joints and prevent leaks. , you may need to use metal wires or ropes to hold heavier showerheads in place. This is a simplified instruction; consult a professional for more details.