1. Find the screen sharing application and put it in the dock for future convenience. It is found at /System/Library/CoreServices/Screen Sharing.app
2. Type that into terminal (it allows you to see netowrked computers that can be controlled):
   defaults write com.apple.ScreenSharing ShowBonjourBrowser_Debug 1
3. Now, to add lots of buttons that are
   additionally found in Apple Remote Desktop, type that as one line into terminal:

   defaults write com.apple.ScreenSharing 
   'NSToolbar Configuration ControlToolbar' -dict-add 'TB Item Identifiers' 
   '(Scale,Control,Share,Curtain,Capture,FullScreen,
   GetClipboard,SendClipboard,Quality)'
4. Now restart screen sharing to see the buttons

Orginal post by WhizzKid