This project provides a KiCad template project which can be used as a convenient starting point for custom electrode boards. It includes connector footprints, placed at the correct locations, as well as the "standard" mounting hole placements used by some other components.
To install the template, check out the project and place it into your
KiCad user template directory. The location of this directory varies on
different operating systems, but you can find it by runnign KiCad and selecting
"Preferences->Configure Paths..." in the menu. You are looking for the value of
KICAD_USER_TEMPLATE_DIR. On linux or MacOS, this is likely to be $HOME/kicad/template.
So, for example:
mkdir -p ~/kicad/template
cd ~/kicad/template
git clone https://github.com/uwmisl/electrode_board_template_100x74