Measure the cabinets and room dimensions
Choose the countertop material
Remove the old countertop
Check and level the cabinets
Make a template if needed
Cut the countertop to size
Dry-fit the countertop
Mark sink, faucet, and appliance openings
Cut the openings
Apply adhesive or support brackets as required
Set the countertop in place
Fasten the countertop to the cabinets
Join seams if there are multiple pieces
Install the sink and faucet
Seal edges and seams with caulk
Clean off excess adhesive or sealant
Inspect the installation for gaps and alignment