No, you don’t need to prepare any plaster cement. All you need is a nail gun, a pipe of silicone, and a pipe of gap filler. Simply cut the cornice into your required size and put some silicone on the back. Then use the nail gun to install the cornice on the ceiling. Last, use gap filler to fill all the nail holes and joints.
If you’re confident in carrying out the installation yourself, no worries! We can recommend a professional installer.