correlative conjunctions and parallelism
Both . . . and, either . . . or, neither . . . nor, not only . . . but also.
After both . . . and, either . . . or, neither . . . nor, and not only . . . but also, use the same form on each side. A noun with a noun: both the notes and the files. An infinitive with an infinitive: not only to write but also to edit. A gerund with a gerund: neither calling nor writing. A finite verb with a finite verb: She neither called nor wrote. Do not mix those forms.
Examples
Use He either signs or waits.
Use not only to file but also to wait
Avoid not only to file but also waiting