Can I use live version from usb and save the things done during the session? Or does it simply come back to original state every time it is opened from live USB?
This might be unknown to many but it is possible to have your settings stored in the live USB. Any changes you make to the system—for example, saving a file to your desktop, changing the settings in an application, or installing a program—will be stored in the overlay file. Whenever you boot the usb drive on any computer, your files, settings, and installed programs will be there.
Ubuntu do supports live use with persistent storage. And elementary is based on Ubuntu so it will work too.
Please follow these steps,
- At first download the iso of the operating system and another software called Linux Live USB Creator.
- Install Linux Live USB Creator. Insert the USB drive you want to use into your computer’s USB port and launch the “LiLi USB Creator” application you just installed.
- Select the USB drive you want to use in the “Step 1: Choose Your Key” box.
- Provide your downloaded ISO file. Click the “ISO / IMG / ZIP” button under “Step 2: Choose a Source”, browse to the .ISO file on your computer, and double-click it.
- Use the options in the “Step 3: Persistence” section to select how much space your want to use for persistent storage on the USB drive. Drag the slider all the way to the right to select the maximum amount of storage.
- You’ve now configured all the settings you need to configure. To create your live USB drive with persistent storage, click the lightning icon under “Step 5: Create”
Above instructions are grabbed from here which shows How to Make a Persistent Ubuntu USB Drive on Windows. However, the process is quite same.