Go to the Streams page from the Sidebar, then click Add Stream.
Then type in a Stream Name. This should be something you may reuse in the future, so for my example I have a folder that contains some files that were collected on my main finish system and named my Stream "Trident File - Finish - Main"
Next select File for the Stream Type
Next select Trident File from the File Type
Next use the Browse button to select the folder that contains the Files you're collecting reads on.
Pick the folder - mine is named "Finish - Main"
You'll see the Folder Path show:
Click save, and you'll see your new Stream show in your list of Streams.