Create a .tar.gz archive in Windows

1. You need the latest 7-zip app from http://www.7zip.org
2. Select the folder that you want to add to the .tar.gz archive. Right click, and select 7-zip > 'Add to archive'
3. You'll need to create a .tar archive first. Choose 'tar' as Archive format
4. Then, right click the newly created .tar archive. Select 7-zip > 'Add to archive' again. This time, choose 'GZip' as the Archive format. For maximum compression, choose 'Ultra' for compression level, and select 258 for 'Word size'. You've successfully create a .tar.gz archive!