First, the installer or designer needs to create a template of the existing counter, this is to give a clear layout of how the new granite countertops will look and fit. The area where the countertop will be installed needs to be cleared of everything including the existing countertop in most cases.
Ask the granite company if the countertop needs to be removed for measuring. If you want appliances like a cooktop installed make sure you consult your designer a few days before the installation so that they can all be installed together. This way you do not run into an extra charge due to having the kitchen countertop experts come out another day.
There are some appliances that need to be purchased separately but the cut-outs need to be done on the installation day. In case the countertop is being installed in the bathroom you may need to remove the mirrors to avoid damage and have them reinstalled after the work is complete.
The granite countertop installation process is usually accompanied by dust and debris so it's wise to cover those appliances you cannot remove and any antiques you might have.
Your pets should be kept away so that they are not a distraction and also to keep them safe from the dust. Before the granite countertop installer arrives ensure you have turned off the air condition or the heating system, this is necessary to prevent dust from spreading to other parts of the house.
For those who have top drawers in their kitchen make sure they are well covered with plastic or a towel or if possible remove them prior to the installation process and set them in a different room.
You can have a plumber or an electrician on hand after the installation to make sure you can have working water after the granite has been installed If you installed under-mount sinks keep it away from water for at least 24 hours.