You can create a personal (viewable only by you) Collection of citations (see below for how) which you can use to add items to course reading lists.
You can sort your collection by date added, author, or title, and scroll through the list to find items, or you can click the search icon to search by title, author, etc.
Once you find the record for the item you want to add, click and drag it into the appropriate section, or click the item to select it and then select the appropriate section and click to "Add" it to that section.
To create, and later to access, your Collection from anywhere in the Library Course Reserve tool, click the lines icon in the upper left corner for the site navigation menu, then select "Collection."
Once you are in your Collection, click to "Add Items" to bring up the options to add items via: