Jmeter: how to save and open project

How to save project:

1. save WorkBench

    Click on File-Save Selections As...

2. create new folder

3. in the same folder save test plan

How to open project:

1. close jmeter
2. run jmeter.bat
3. open test plan: click on File-Open
4. open workbench: click on Workbench, click on File-Merge

More information is here