I've had great luck using an electric carving knife. No force is required, you can do it standing up and it'll cut right angles to accommodate electrical outlets.
Subscribe to Fine Homebuilding magazine now and save up to 52%
© 2017 The Taunton Press, Inc. All rights reserved.
Become a member and get instant access to thousands of videos, how-tos, tool reviews, and design features.
Start your subscription today and save up to 52%