Download and install [https://sourceforge.net/projects/winpython/files/WinPython_3.6/3.6.6.2/ WinPython]
After you install that, open a terminal window and do:
''' cd \Users\USERNAME\Downloads\WPy-3670/scripts'''
and then
'''pip install ledgerblue'''
Download the [https://raw.githubusercontent.com/traysi/ledger-app-rvn/master/bin/app.hex app.hex app file for Ravencoin].
Open plug in and unlock your Ledger, then open a terminal copy the app.hex file to the folder you are in, and say do '''pip install ledgerblue'''
Then navigate to the folder where you downloaded the app.hex file and do '''python3 python -m ledgerblue.loadApp --appFlags 0x40 --apdu --tlv --targetId 0x31100003 --delete --fileName app.hex --appName "Ravencoin" --appVersion 1.3.2 --dataSize 0x00000000 --icon 0100000000ffffff00ffffffffffff1ffc0ff80fe107c0078003f003f807f81ffc3ffcfffcffffffff'''