documentation is here: http://michele.sciabarra.com/2016/06/17/scala/ScalaGoodies/

In short:

git remote add ScalaGoodies https://github.com/sciabarra/ScalaGoodies
git fetch --all

If you want an advanced sbt:

git merge ScalaGoodies/esbt

If you want Scala completions and reformatting with Atom:

git merge ScalaGoodies/completion

If you want a notebook, both external (Jupyter) and internal in Atom (Hydrogen):

git merge worksheet

Then complete with

bin/install.sh

That's all.