How to recover accidentally deleted projects

You can scavenge the volume with a data recovery utility like Prosort Data Rescue (Mac Data Recovery Software - Data Rescue - Disk Recovery Tool ).  If it's a very recent delete and you haven't use the drive much, there's a good chance that you can recover the file.  There's a demo version that allows you to analyze your drive for free and preview recoverable files.  Prosoft also makes a PC version.

Although, if the drive's had regular use since the deletion of the file, I often compare recovered the files to being like the pets in Stephen King's Pet Semetary: Smucky the cat comes back, but not quite the same as before.  Or, more specifically, you've recovered your deleted QuickTime movie file, but the pixels scatter all across the screen when you press play.

Use versions and backups.

I tell my students: Disk space is cheap, good work isn't.  

Incremental Saves, auto-save, cloud save.

The Forum Lounge is not for technical help, please provide the name of the program you are using so your message may be moved to the correct program forum

Most programs have auto save.

Then again you should not trust just auto save, make sure you make copies of important project to another drive.

But which program are you revering to?