Part 1 (Gateway)

The final step of this guide is to install arm9loaderhax and setup CakesFW to run just milliseconds into the boot. This is accomplished by using SafeA9LHInstaller by AuroraWright, then setting it up to work with BootCtr9, a boot manager that lets us load things on boot.

This will install Delebile's Fork of arm9loaderhax.

If you currently have Updated SysNAND + Cakes/Updated SysNAND + Luma3DS and want to switch to Gateway, just follow "Preparatory work" and "Part 2"

Don't update your SysNAND or you will brick on N3DS/O3DS will lose arm9loaderhax

There is a special Arm9LoaderHax installer for Gateway. However, we will not be using that for the following reasons

We will also setup the ability to launch HourGlass9 from arm9loaderhax, giving us the ability to unbrick our SysNAND from situations that would normally brick us by restoring from backup.

What you need

• data_input.zip (mirror)
• payload_input.zip (mirror)
• slotkey_input.zip (mirror)
• boot_config.ini
• The latest release of BootCTR9
• The latest release of hblauncher_loader
• The latest release of HourGlass9
• The latest release of HBLauncher_loader
• The latest release of EmuNAND9
• The latest release of Gateway
• The Gateway arm9loaderhax.bin file
• The latest Stable release of SafeA9LHInstaller
• The latest release of Uncart for arm9loaderhax

Instructions

Section I - Preparatory work

2. Delete the Decrypt9 folder from the root of your SD card if you have one
3. Copy the a9lh folder from data_input.zip to the root of your SD Card
4. Copy and merge the a9lh folder from payload_input.zip to the root of your SD Card
5. Copy your console specific OTP.bin (the one you got in Part 4) to the /a9lh/ folder on the root of your SD card
6. Copy and merge the 3ds folder from the SafeA9LHInstaller zip to the root of your SD card
7. Copy SafeA9LHInstaller.dat from the SafeA9LHInstaller zip to the root of your SD card
8. Copy arm9bootloader.bin and arm9loaderhax.bin from the BootCtr9 zip to the root of your SD card
9. Copy hblauncher_loader.cia from the hblauncher_loader zip to the root of your SD card
10. Copy boot_config.ini from the "What you need" section above the to the root of your SD card (not from the BootCtr9 zip)
11. Copy Decrypt9WIP.bin from the Decrypt9WIP zip and arm9loaderhax.bin from the Uncart zip to the /a9lh/ folder on your SD card
12. Rename arm9loaderhax.bin from the Uncart zip in /a9lh/ to uncart.bin
13. Copy the contents of slotkey_input.zip to the root of your SD card
14. Copy and merge the 3DS folder from the EmuNAND9 zip to the root of your SD card
15. Copy EmuNAND9.bin from the EmuNAND9 zip to the /a9lh/ folder on your SD card
16. Copy your emuNAND_original.bin backups from Section I to the root of your SD card
17. Copy over launcher.dat from the Gateway 3DS zip to the root of your SD card
18. Copy over the arm9loaderhax.bin file to the a9lh folder on your SD card

Section V - Restore EmuNAND

11. Shutdown holding Down+B, then open HourGlass9 from arm9loaderhax by holding Start on boot
12. Go to "EmuNAND Backup/Restore..."
13. Select "NAND Restore"
14. Confirm and restore from emuNAND_original.bin

#####Section VI - Finalizing setup

1. Reinsert your SD card into your 3DS
2. From EmuNAND Manager Options, make a backup of SysNAND to sysNAND.bin
3. Press Select on the main menu to eject your SD card, then put it in your computer
4. Rename sysNAND.bin to sysNAND-A9LHAX.bin, sysNAND.bin.sha sysNAND-A9LHAX.bin.sha, and copy both to a safe location on your computer; this is a SysNAND backup containing arm9loaderhax
5. Delete sysNAND-A9LHAX.bin and sysNAND-A9LHAX.bin.sha from your SD card
6. Reinsert your SD card into your 3DS then press Start to reboot
7. Update your Emunand to the latest version using system settings (if it is not already)
8. Open Health and Safety (which is now FBI)
9. Select "SD"
10. Navigate to hblauncher_loader.cia and press A to install
11. Navigate to lumaupdate.cia and press A to install
12. Exit with the home button
13. Launch the Homebrew Launcher from the home menu icon at least once to ensure the payload is functional
14. Reboot!

If everything has gone according to plan, arm9loaderhax will be installed to your device, you will have a CIA installer, and you'll be able to launch the Homebrew Launcher from an icon on your home menu. Your device will now automatically launch into EmuNAND.

You will no longer be able to boot without the SD card in, that is normal.
You will now boot EmuNAND by default.
You can now hold Select on boot to launch the Luma3DS configuration menu.
You can now hold Start on boot to launch HourGlass9, a full featured NAND tool.
You can now hold Y on boot to launch EmuNAND9, a full featured RedNAND and SD management tool.
You can now hold X on boot to launch Uncart, a tool for converting a physical game cart to an installable file. (in the linked guide, replace Brahma with arm9loaderhax)

You can now update to ShadowNAND