Catalog Manager gives you the following options for editing your products:
To edit existing products one at a time:

Editing selected products using the "Edit Selected" option
The "Edit Selected" option is a new feature in Catalog Manager designed to save you time, by letting you make the same changes to multiple products at the same time, in just a couple of clicks.
For example, if you'd like to apply a discount to a few of the products in the same table, you may do this by selecting these products using the checkboxes, clicking "Edit Selected," and making edits to the discount attribute using the "Edit Selected Products" screen.
The "Edit Selected" button is disabled until one or more products are selected using the product checkboxes located in the product table column to the left of the ID column. The "Edit Selected" option can only be used for editing products in individual tables, and will be disabled if "all-tables" is selected.

To update multiple products in a table using the "Edit Selected" option:

If you wish to make the same changes to all items in a table, you can quickly select all items in a table by doing the following:
Editing all products displayed onscreen, using the "Edit All" option
The "Edit All" option replaces the former "Edit These Items" option, letting you open all products displayed onscreen for editing. For example, if your table is set to display 25 products per page, then clicking the "Edit All" button would open all 25 of these products for editing. Unlike the "Edit Selected" option, the "Edit All" option allows you to make individual attribute changes per product listed. The "Edit All" option may be a more efficient editing option than editing products one at a time in cases where multiple products in a table require different attribute changes.
For example, if ten products in a table need updates to different attributes, you can save time by opening all of these products for editing, making only the changes needed for each product and saving all of the changes at the same time, rather than opening each product for editing one at a time, and making and saving changes to these products one at a time.

Editing products using a spreadsheet upload
Products may also be edited by downloading a table spreadsheet, making your desired changes, and uploading the updated spreadsheet using the Upload/Download tab. To learn how to upload and download spreadsheets, please see our Upload/Download help page.