I want to preface this by saying that the version that your WordPress instance is currently loading is the version that instance has been tested against, and you may experience unpredictable results using a newer untested version, which may not be compatible with other jQuery scripts, plugins, etc.
However, if you still want to use the newest version of jQuery and you are not reasonably knowledgeable about manipulating your theme function.php file directly than you should use the
jQuery Updater Plugin
which will load the latest stable version of jQuery and override the version used by WordPress for non-admin areas of the site controlled by your theme and plugins.