You have two ways to connect your Dropbox account and publish content.
Dropbox in the Audio Inbox
Head to https://app.helloaudio.fm/audio-inbox and click Authorize Dropbox. Sign into your Dropbox account and navigate your media files from there.
Select the files you'd like to import, then choose the feed, and send them over. They'll appear inside the feed as new episodes ready to publish.
Dropbox as the File Selector
Above the list of episodes in a feed you'll find "Add form Dropbox". That will open a window to your Dropbox account after signing in and allow you to select files you'd like to add to the feed.
Choose your files and they'll be migrated into the feed as new episodes. Done!