Slide the grips off your handlebars. You can remove the left grip and right throttle grip by simply grabbing them and pulling them off the handlebars. You may have to rock the grips while pulling in order to break the suction seal before they will come off.
Use the screwdriver to loosen the clamp holding the brake lever to the handlebars. The small screw is underneath the clamp band. Pull the brake lever off.
Pry the covers off the Allen bolts holding the handlebars in place. The Allen bolts are set in a plate in the center of the handlebars, near the gas tank.
Use the Allen wrench to loosen the bolts in the holding plate. The plate is made of two halves that are held together by the pressure of the bolts and locking the handlebars in place between them. The two plates will separate, and you can slide the handlebars out from between them.
Insert your new handles between the plates, and tighten the Allen bolts. Reverse the rest of these steps to complete the installation.