Before building the website, all the agency developers, including myself, gathered and discussed the different technologies to use, and how we would split the work load between each of us.
After deciding which component(s)/page(s) everyone had to build, we set up a Git repository to easily collaborate and manage code history.
After that, we each worked on our assigned chunk of the website and committing the changed regularly to the GitHub repo, so that other people could keep track of what had been completed, and what remained to be built.
I personally took care of the markup and styling of the landing page, as well as the error page.
I also took care of implementing the mouse follower and the page transition with barba.js.