Where To Begin

Sometimes, it's a good idea to just start from scratch. Think about some custom HTML/CSS theme or layout files you've already created or used before in a non-Mura project. What did the basic structure look like? Generally, there's some type of basic directory structure in place. The following basic structure is not uncommon:

/css/{your css files would be in here}
/js/{your JavaScript files would be here}
index.html