In order to install an image, you must identify your device ID.
Check it as follows:
blkid -o list
Image
Each device has numbers at the end, those numbers are related to partitions and are not needed to install the image. As example, instead of /dev/sdb1 use /dev/sdb.
Installing
Yocto supports several image formats, as example ext4, img, sdcard and wic.
In old Yocto versions, the most common image type was sdcard, use dd with this image type.
sudo dd if=<image.sdcard> of=/dev/<device> bs=4M && sync
Recent Yocto versions have wic image type as default format, use bmaptool as follows:
sudo bmaptool copy <image.wic> /dev/<device> --nobmap