There are many excellent books on proofreading. Here are a few that we recommend:
The Elements of Style, by William Strunk Jr. and E.B. White
The Chicago Manual of Style
The Associated Press Stylebook
These books will help you develop a strong understanding of the basic rules of grammar, punctuation, and style. They will also give you a good foundation on which to build your own proofreading skills.
In addition to these resources, there are many online guides and tutorials that can be helpful. Here are a few we recommend:
The Purdue Online Writing Lab's Proofreading Guide
The U.S. Government Publishing Office's Style Manual
The University of North Carolina at Chapel Hill's Proofreading Tips
With practice and patience, anyone can learn to proofread effectively. These resources will help you get started on the path to becoming a great proofreader.