1. Please format the SD to fat32 or vFat firstly.
2. After formatting SD card, insert SD card into camera, it will automatically start recording. And after 5 mins, it can playback.
The maximum storage is 128GB. Once it goes full it will overwrite it, so the recording will be continuous.
Notes: Before pulling out SD card, please cut off device power! Otherwise, it might be damage SD card and lose data.