When you select an item from one of ClipMate's ClipLists, it is automatically placed onto the clipboard. There is no "copy to clipboard" required - it's automatically done as the clip is selected. If you are in ClipMate Explorer, the list of clips is right there. If you are in ClipMate Classic, then there is a drop-down arrow that exposes the ClipList.
Sometimes you need to perform an action (deleting, printing, etc.) on more than one clip at a time. This is easily done by holding down the SHIFT key and clicking on two clips with the mouse. This selects the entire range of clips. Or you can use the CTRL key, and pick and choose the clips that you need.
For quickly accessing clips that you use frequently, you will want to look into ShortCuts. To quickly access a clip where you know part of the title, you can recall it within the current collection with the QuickPick technique.