Currently, 1-more-clip is single user only, meaning that you can't share your clips on multiple computers.
What you can do though, is to transfer a database from a mac to another.
- On the 'old' mac, go to ~/Library/Containers/com.1-more-thing.clip/Data/Library/Application Support/1-more-clip/
(you can press Shift-Command-G from the Finder if you don't know how to access your Library folder)
- Copy the file "database.sqlite"
- On the 'new' mac, launch 1-more-clip if it was never launched before
- Quit 1-more-clip
- Paste the file "database.sqlite" in the corresponding location
- Launch 1-more-clip again