Fresh was born on that sinking feeling we have whenever we head into the Finder to 'Find' that file that we are working on, just downloaded, or like to keep handy. Fresh is designed to hide itself when you are not using it - keeping your onscreen clutter of windows more managable.
Two Main zones.

There are two main areas in Fresh. The top one shows files that Fresh has identified as new to you, currently being edited, etc. When you download a file from the internet, or save an attachment in Mail, or edit a file in Word, it will show up here. As new and changed files appear on your computer, then are added to this area. If you click on an item, then press the delete key, then that item is simply removed from the list, with the file on disk left alone. To throw a document into the trash, just press 'command - delete' or drag it to the trash can in the dock. Since new items will be appearing in the 'Fresh Files' area all the time, if you see a file there that you will be working with today, just drag it into the 'Cooler' below.

Tagging and Searching.
Fresh can tag files - to tag a file simply select it (or multiple docs) then press the return key. You can pick from recently used tags, or simply type in tags. To move onto the next document, press the 'tab' key. You can also rate files with 1 to 5 stars. Spotlight searching for items that you have tagged is easy, just bring up the search dialog (command - F), and then click on or type in the tags you plan to search on. Search results are displayed in the Finder for further fine tuning or browsing.

Tips and tricks.
Fresh uses a large window so you can see the files that you are dealing with, but keep in mind that as you drag something out of Fresh, the window vanishes, leaving you with plenty of space to complete your drag.

In the Fresh zone, you may see 4 to 10 items listed, depending upon your monitor size. Fresh actually keeps track of more items than this - you can use the arrow keys to look a bit farther into the past. Same thing applies to the cooler. As you add items, other items will drift out of view. Fresh allows you to go back and find items that have recently fallen off the front view. Don't forget that in the cooler you are free to rearrange the order of the documents as you see fit.

There is a menu available for each document that allows you to see the path of the item. In the Fresh zone you can also use this menu to add exclusions: You can exclude all files of a certain type, specifically that single file, or exclude any folder. This allows you to keep unwanted files from appearing in Fresh. You can edit these exclusion settings in the preferences.