Unity has its starter shortcuts here:
Copy one of these shortcuts and edit it by right clicking.
If you need multiple commands to start an application, put them in a textfile and save it in your home directory with an sh extention. Make the file executable (using nautilus: right click, properties, rights --> make executable)
For example, You need to make a starter for Skype using a preload for enabling the webcam.
The needed preloading of a video4l driver for skype video works as follows:
as root make a textfile with this command in a terminal:
gksu gedit /usr/share/skype/skype-video.sh
enter as text:
save it and exit gedit.
(other possible preloadings are found here.)
select the textfile, select properties, rights and make it executable
Still in root-nautilus:
navigate to /usr/share/applications
and look for the skype shortcut. Copy and paste the shortcut. Rename the second one to skype-video.
Right click on it and select properties. Change the command to /usr/share/skype/skype-video.sh
Drag and drop it to the unity bar and you should have a shortcut working.