1. Place the following code on your site, under the <head> tag:

    <script>
    function OpenWindow(url, windowName) {
       newwindow = window.open('https://druzi.uk/sharer?url=' + url, windowName, 'height=600,width=800');
       if (window.focus) {
          newwindow.focus();
       }
       return false;
    }
    </script>                        

  2. Once placed, pass your site url to the function, example:

    <button onclick="OpenWindow('http://yoursite.com/')">Click me</button>

  3. Example for test: