From charlesreid1

Create a config folder using the --generate-config flag, then start the notebook using the default config directory:

$ jupyter notebook --generate-config
Writing default config to: ~/.jupyter/jupyter_notebook_config.py
$ jupyter notebook

Alternatively, create a config directory somewhere else, and start the notebook using that non-default config directory:

JUPYTER_CONFIG_DIR=~/jupyter_custom jupyter notebook --generate-config
JUPYTER_CONFIG_DIR=~/jupyter_custom jupyter notebook

Example: Jupyter/Base16