Kohler faucets are high end metallic pieces marketed to commercial and home clients. These faucets are typically composed of a handle, ball bearing, cartridge and two rubber rings. These parts are well made and if installed properly can last for many years. You will need to disassemble and remove the old faucet if you are replacing it or need to access the water lines that lead to the rest of the room. Many of the parts for a Kohler faucet are reusable if properly cleaned.
Search under the sink or cabinets for the water main control. The water main controls the flow of water to all the pipes in the same room. You can identify the water main as one or two handles attached to a flexible metallic pipe or copper pipes.
Turn the handles of the water main at least half a turn to the left to shut them off.
Push the faucet handle all the way into the "up" position. This will expose a star-shaped hole on the bottom of the handle.
Insert the hex key into the star-shaped hole and turn it counterclockwise until the faucet comes loose.
Remove the faucet handle from the assembly. This will reveal several loose pieces including the ball bearing and cartridge. Remove the ball bearing with your hand.
Use the pliers to grasp the cartridge and turn it counterclockwise one half turn, and then pull it out.
Pry the rest of the faucet assembly off with your flat-head screwdriver. You can also use the screwdriver to remove any caulking and pop out the two rubber rings.