The instructions I usually point to are,
Memory Upgrade Mod Guide. They are for the Glo, but the basic steps and tools are the same.
But, you don't need to format the card first. The image writing does that. And there should be three partitions. Something to try is a manual factory reset. See
https://help.kobo.com/hc/en-us/artic...our-Kobo-Touch for instructions. This will frequently solve problems after using the images.