rxTools

I. Initial setup
1. Backup Nintendo 3DS folder to PC
2. Download latest Gateway release at http://www.gateway-3ds.com/downloads/
3. Download slot0x25KeyX.bin
4. Copy slot0x25KeyX.bin to sd:/root
5. Copy launcher.dat to sd:/root
6. Go to http://go.gateway-3ds.com
7. Backup sysnand
8. Copy nand.bin to PC
9. Format emunand
10. Copy Nintendo 3DS folder and files back to the SD card

II. rxTools installation
1. Download latest rxTools build
2. Download firmware.bin using /tools/cdn_firm.py
3. Copy firmware.bin into rxTools/sys/
4. Delete rxTools.dat, firmware.bin and rxTools directory from SD card(if it exists)
5. Copy rxTools directory into sd:/root
5. Copy slot0x25KeyX.bin into sd:/root
6. Go to http://dukesrg.github.io/?rxTools/sys/code.bin
7. Wait until installation finishes and then boot to rxTools emunand once

III. Unlink nands
1. In sysnand, go to System Settings -> Other Settings -> Format System (Do not accept yet)
2. Eject the SD card
3. Accept system format
4. After it reboots, go through the setup screen and set everything up
5. Once in the home menu, insert the SD card and let it create some files on the card
6. Nands are now unlinked, and there are 2 ID folders in your Nintendo 3DS folder on your SD card (one for emunand, another for sysnand)

IV. rxTools MSET installation
A. rxinstaller.bin Method
1. Copy the rxinstaller.bin from the mset folder into sd:/root
2. Restart your 3DS
3. Go to http://dukesrg.github.io/?rxinstaller.bin
4. Once the bottom screen flickers, press Home and you will see an error message (dismiss the error message)
5. To access rxTools MSET, Go to System Settings -> Other settings -> Profile -> Nintendo DS Profile

B. FBI/ROP Injection Method
1. Go to http://dukesrg.github.io/?rxTools/sys/code.bin
2. Go to Advanced -> Inject FBI -> Emunand -> Check TMD Only
3. Take note of TMD version and console region
4. Copy fbi_inject.app and fbi_inject.tmd from rxTools/tools/fbi_injection/CONSOLE REGION/TMD VERSION/ to sd:/root
5. Download latest FBI build https://github.com/Steveice10/FBI
6. Copy FBI/home/.../FBI.cia to sd:/root
7. Go to http://dukesrg.github.io/?rxTools/sys/code.bin
8. Go to Advanced -> Inject FBI -> Emunand -> Inject FBI
9. Boot rxTools emunand
10. Open Health & Safety Information
11. Install FBI.cia
12. Return to Home and open FBI
13. Press Select
14. Locate rxTools 3.x (console version)
15. Press A and restart once installation is finished
16. To access rxTools MSET, Go to System Settings -> Other settings -> Profile -> Nintendo DS Profile

IV. FBI Installation
1. Follow steps 1-11 of rxTools MSET installation via FBI/ROP Injection
2. You can now install CIAs

* FBI installation - Invalid database error
1. Create a blank text file called import.db and title.db in Nintendo 3DS/ID1/ID2/
2. Boot to emunand
3. Go to System Settings -> Data Management -> Nintendo 3DS -> Software
4. Press Accept to rebuild software database
5. Reboot to emunand before proceeding with FBI installation

V. Emunand
1. Backup emunand
2. Update emunand

Backing up emunand
http://www.maxconsole.com/maxcon_forums/threads/285550-Backup-Restore-of-Emunand-when-upgrading-replacing-SD-card