To set up a training site for demo purposes use cloudaccess.net free for the first 30 days and then you need to renew.
use the /templateDetails.xml in the Helix template to rename the modules so they are easier to find or add new module positions.
Style to change Background Colour
Padding via cog
Set to Fluid for full width screen
Footer details can be found in Basic
Don't use Logo in Basic, use Module position instead
SPPagebuilder is worth purchasing to use in conjunction with the Helix Template.
Install Blank Component to assign a blank page to a menu link for training purposes only.
To change CSS code go to the item and right click and then inspect and then copy the code into Custom Code > Custom CSS > paste code and change e.g. hex colour
Backup of the helixtraining site can be found in Google Drive backups