Atmosphere already set up and installed. If not, use my guide here, skip the blanking your serial number page.
Tinfoil already set up and installed. If not, use my guide here.
A NAND backup created and stored somewhere safe not on your SD card. If not, use my guide here.
Step 1. Download
exosphere.ini from here, if it opens as a page, right click the empty space, and save it to your desktop. Make sure the file ends with
.ini (this config file is what we'll use to allow cal0 writing to run Incognito in Tinfoil.)
Step 2. Right click
exosphere.ini and open it in a text editor (NotePad++ is my personal choice on Windows.)
Step 3. Edit
allow_writing_to_cal_sysmmc=1 (this option enables cal0 writing for Tinfoil's Incognito to work.)
Step 4. Save the file and place it on the root of your switch SD card (Atmosphere reads this config file from the root of your sd card.)
Step 5. Put your SD card back in your switch and boot it with fusee-primary.bin . Launch Tinfoil and navigate to the
Incognito tab near the bottom. Highlight your serial number in the right space.
Step 6. Press
Y on your controller. Tinfoil will warn you about if you forget your password, the backup isn't valid. Either set the password as nothing or something simple like
1. This is why also I strongly recommend to have a NAND backup, as you can pull your serial from there in case this happens too.
Step 7. If ran correctly, Tinfoil will tell you Cal0 writing worked. Restart your switch and verify this by going in
Serial Information. Your serial number should look similar to the image below.
You may delete
exosphere.ini from the root of your SD card if you wish now too. Incognito is permanent unless you restore your serial with Tinfoil or a backup.