hello everyone, i want to send files via email to someone so they can download it and work on it. can someone please give me step by step how to do this.
thank you all

There are a lot of variables. Please describe exactly what you are tying to do and I'll try to help with my limited knowledge but it will also help those more experienced give you a definitive answer. For now set yourself up a file sharing service account such as dropbox. Most email providers will not allow you to upload files that large.

General stuff...

Are they using Sonar as well? If so do they have the same version as you?

You will want to make sure the people receiving the files import them into a project that use the same bit depth, samplerate and meter (bpm's).

Their hardware will obviously have to be capable of handling higher samplerates and bit depths if you are going above 44.1k/16 bit (some interface don't handle higher settings and if their computer sucks it may not be able to process the data).

If they are using a different DAW software you should read up on OMF exports in the Sonar manual and in general.

... etc.

If they are merely laying down a take and not mixing anything you can just send them a stereo file or if you want to allow them to adjust certain elements you can export individual busses to create "stems" and then they can adjust some levels.

Be sure to "compress" (not audio FX compression... data compression like a zip file) so it doesn't take as long to upload/download the files.

... etc...

If you are using specific audio FX or soft synths that the receiver do not own bounce the MIDI and FX to audio because otherwise they will not have access to them.

and that's all I can think of for now... Cheers.

You still there?

If you are going to send a whole mix and they have Sonar read up on .CWB (batch) files. That will send them a duplicate of everything but it will be HUGE. 

Seriously some details would help.

 Must be on a coffee break

https://www.dropbox.com/

https://www.yousendit.com/

Many others as well available

@Mike... Indeed. It happens though. I've actually spent some time looking into this subject because I need to do this type of thing in the very near future so I might actually be able to give a step by step (oooh baby... sorry) for once. The forum has helped me so much so now that I'm taking a break I'd like to pay it forward as they say. ;-)