In StitcherAds once URL parameters are configured in the "Settings" menu they are added to all your ads by selecting the option to 'add URL parameters'.
*Note - As of October 2015, URL Parameters are now added to the "optional URL tags" setting as opposed to being hard-coded onto the end of the actual URL.
Setting up URL Parameters
Go to Settings>Advert Tracking>URL Parameter settings
On the setup page you'll see the example parameters box at the top - this gives you a preview of the URL parameters you are creating.
Below it you can see both StitcherAds parameters and static parameters.
Static URL Parameters
Static URL Parameters do not change across the variations of your adverts. You should use these to input parameters such as your Google utms e.g. utm_source that do not change.