how do i free disk space on my macbook air

See this FAQ: http://www.thexlab.com/faqs/freeingspace.html

also, this: http://pondini.org/OSX/DiskSpace.html

Well, iTunes is a start. It duplicates your songs. (at least with me) try looking for the duplicates and deleting them. Second, iPhoto is the DEVIL!

I have a MBP mid-2010 with 250g hard drive, and i freed 30g of space cleaning out duplicate pics that iPhoto makes. There is another 10 I have an option of cleaning, but those are very important to me, so I chose not to.

That's about it.

Btw, check your applications folder and delete anything uneccesary.

You may also find this Link of Interest...

http://macmost.com/what-to-do-when-your-hard-drive-is-full.html

One thing that saved me about 23 gb was cleaning up the ipod photocache folder. Something I did not read through the numerous "clean your harddisk" websites, but by looking at the large files on my MBA 250Gb through OmniDiskSweeper. Read more here: http://support.apple.com/kb/TS1314?viewlocale=en_US&locale=en_US