The best way to comment on a CEQA document is in writing. This can be done during the public review period for the proposed Negative Declaration or draft EIR. Written comments can also be submitted at the hearing held on the project.
Local projects typically require a public hearing. The findings of the CEQA document will be one of the factors taken into consideration by the agency decision makers when deciding whether or not to approve the proposed project. Verbal and written comments can be submitted at the hearing. Written comments are best because they are more accurately entered into the record.
If there is litigation over the project, the scope of the litigation will be limited to information that is in the record. Further, unless an issue is raised during the CEQA process or at the public hearing it cannot be raised in litigation.