Locate your catalog (LrC).
After knowing where you have stored your photos, you will need to know the location of the Lightroom Classic Catalog file. It is stored by default in a Lightroom folder within your Pictures folder. The default preference is to load the most recent catalog. This means that if ever you opened another catalog (like an older backup copy or a small catalogue you exported), and then closed LrC out, it will open that catalog the next time LrC launches without you realizing. I’ve seen some people spend months working in an old backup catalogue and then not realizing it until they deleted all their backup catalogs and their work disappeared. You can find the filename and location of an open catalog by going to Lightroom Classic > Settings > Catalog (PC: Edit > Settings > Catalog > General). You can then move the file to a new location if necessary.
Label Folders and Collections with Colors (LrC).
You may find it useful to color label your folders or collections in addition to naming them meaningfully. This will help you to better visualize the contents. As with photos, you can assign any folder, smart collection or collection set a color label in red, yellow or green. Click the folder/collection to add a color label. Then, choose the color you want.
Marking a folder as a favorite (LrC
You can mark folders favorites in addition to color labels and names. You can use color labels for a variety of reasons, such as to create a workflow, (red = in progress work, green = ready for delivery) or to describe the contents, (blue = HDR and purple = portraits). But you may also want to mark certain folders to represent important work, favourite locations, family members or other special meanings. Marking a folder a favorite is as simple as right-clicking the folder you want to mark and selecting Mark Favorite in the contextual menu. All folders that have been marked as favorites are indicated by a little white star.
Favorite a collection
The same can be said for folders that contain photos of special significance. However, there is no contextual menu to mark a collection as a favorite in the Collections Panel. Select the collection that you wish to mark as your favorite. Then click on the name of the collection above the thumbnails and select Add to Favorites. The star icon is not displayed on collections that are marked as favorites, unlike folders. However, all folders and collection marked as favorites appear in a group called Favorite Sources.
Filtering the folders and collections panels (LrC).
If you type in the small field at the top of the Folders or Collections panel, the panel will only display folders and collections that match the text you entered. If, for example, you start your folder names with dates, then typing in the year will only show folders that are from that particular year. You can filter each panel using the color labels by clicking the magnifying glass icon. For example, you could label all the collections of a client in a certain color and then filter by the color label to only display their work. Folders panel allows you to filter by Favorites (this is not possible in Collections Panel) and Collections panel offers the option of filtering Synced Collections.