The steps for printing from the micro SD card are available on this Wiki
The X1/X1C supports a micro SD card of up to 2TB if formatted using the printer option.
Our printer will only use 85% of the micro SD card's memory at most. When the memory of the micro SD card is occupied 85% or more, the video cannot be recorded. If the remaining micro SD card memory exceeds 15%, you can record printing videos until 85% of the micro SD card memory is occupied. After that, the new video will flush out the old video.
The printer supports FAT32 format only. For Windows, the default format would be exFAT if the micro SD Card storage is over 32GB, while there is no such limitation for Linux and Mac. If you want to use a 64GB to 2TB micro SD card, you could format it to FAT32 using Linux or Mac system or the printer.
You will only get notifications on the Handy app when you send a plate using the cloud from the Bambu Studio;
The printing through a micro SD card bypasses the cloud server. Therefore, it is not processed through the cloud; normally, you don't get any notification if you are using a micro SD card; that is currently how printing through a micro SD card works.