Note: this is specifically meant for the MacOS edition.
In Acrobat Reader, choose Preferences… -> Signatures -> Identities & Trusted Certificates: More…
In PKCS#11 Modules and Tokens, choose Attach Module
- for versions > 5.6, use
/Applications/Personal.app/Contents/Frameworks/libtokenapi.dylibas path - for versions older than that, use
/Applications/Personal.app/Contents/MacOS/Personal
Eventually it would look like:

