how to send large file other than by dropbox?

ftp transfer is one alternative, but if you want serious help, provide details on how large the files are, etc.

This service lets you send up to 2 GB at one time, at no cost.

https://www.wetransfer.com

I think currently the best way is to use Filemail. Main reason: they offer significantly larger free limits than other services (any number of files up to 30 GB each for free):

http://www.filemail.com/

The transfer speeds are great, and Filemail also has a mobile app for sending large videos from your iPhone / iPad to any e-mail.