1. Go to the App Store search for OpenVPN Connect and Install it.
Because of iOS limitations, you will need to do step 2 and 3 on your computer.
2. Download the OpenVPN iOS BTGuard Configuration Zip.
3. Unzip the downloaded file and email yourself the ovpn file.
4. Open that email on your phone and tap on the attached ovpn file.
5. Tap on Open in OpenVPN
6. Tap on the + button