Quick question

Now this may be a stupid question but I have to ask it anyway. I am new to blender and have been watching some tutorials. I noticed that in alot of them the persons toolshelf and properties panel,the one with n for a hotkey, are see-thru, but I cannot seem to figure out how to do this. Can someone please let me know how? When I open these it makes my editing window smaller and I would like the extra space. Thank you for your time.

User preferences -> system. Enable triple buffering and region overlap.

File / User Preferences / System. Enable ‘Region Overlap’ so the 3d view doesn’t change size when you open the two panels

File / User Preferences / Themes / 3D View. Under the Theme Space Settings change the colour and transparency of the ‘Region Background’ option to change these panels transpareny