What data are you looking to move?
Some apps let you move their data to the SD card via their settings.
Most apps don't let you do this.
If you are talking about user-created files (music, videos, pictures, documents), then use your favorite file browser app:
- create a folder on the SD card.
- COPY (not MOVE) the files to this new folder on SD card.
- Verify that the copy was successful. (Restarting the phone can be helpful but overkill.)
- Delete the original files from the internal storage.
Repeat the above as need.