Watchers can be edited in any of the following ways:
Double-clicking on the relevant watcher area on the Time Line will open the Watcher window to allow you to modify it as required. Note - Watchers are not visible on the Time Line by default. Clicking the Show Watchers button on the Calendar Controls will make Watchers visible on the time line, allowing you modify them, or see Watchers created by other users.
Double-clicking on the relevant entry in your My Watchers list will open the Watcher window to allow you to modify it as required. See My Watchers for more info.