Here is a quick tutorial on creating an Application Icon from a Bookmark and move it to the Dock.
1. Open “Automator” Its located in the Application Folder.
2. We are going to create an Application (Select Application)
3. Open Safari and type your preferred URL in the Address Bar. We are going to use Youtube.com in this example.
4. Drag it to the Desktop and Copy it to the Application Folder or Drag it straight to the Application Folder
5. Go back to Automator and Select “Files and Folders” under Library on the left.
6. Select “Get Specified Finder Items” and drag it to the main window.
7. Select “Open Finder Items” and drag it to the main window.
8. Under “Get Specified Finder Items” click “Add” and Browse to the Youtube file that you copied to your Application Folder.
9. Time to Save your new Application. Go to “File > Save” name your App “Youtube” and Save it in Your Application Folder.
10. You can use Google’s Image search to find a nice icon for your App.
11. Open your downloaded icon and with Preview > Select All > and Copy.
12 Right click on the newly created Youtube Application and click “Get Info” > Click the little icon on the Left > and Paste in your new icon.