The steps are the same that you write
1. Open "Software & Updates"
2. Go to "Other Software" tab
3. Click on "Add..."
4. In the "APT Line" Textbox write the PPA source (example: ppa:libreoffice/ppa)
5. Click on "Add Source" button
Check the file created on /etc/apt/sources.list.d/ppa-name.list
Hi Brian
The steps are the same that you write /ppa)
1. Open "Software & Updates"
2. Go to "Other Software" tab
3. Click on "Add..."
4. In the "APT Line" Textbox write the PPA source (example: ppa:libreoffice
5. Click on "Add Source" button
Check the file created on /etc/apt/ sources. list.d/ ppa-name. list