New to Devonthink Need Help

Hi all, I have purchased and installed deveonthink 2 and have the following question. I have my files and folders on my drive or on Dropbox. I have imported some of those files into a new database that I am establishing. If I save new files to a an existing folder on the harddrive or on my Dropbox what is the best way to add it to the database? Do I have to manually search and see which files are not on the database and import them? Or do I just copy the entire folder into the database again? I have read the issues regarding the database and dropbox and plan on having the database saved on my HD and will move it in between computers using a flash. Your help and advice is much appreciated.
thanks

If you index the folder, then synchronize it from time to time (File > Synchronize) to update the files in your database. If you import files, then you’ll need to import new ones. Don’t import the whole folder, unless you want to continually add duplicate files to your database.

Only you can decide which files to import and when.