If you already have a git repository made, you can skip this step. Otherwise you need to set-up a git repository. This is not difficult, but it is dependent on what you name your git repository. See this

Unless you like vi you will want to set your basic editor. I suggest doing:

git config --global core.editor "nano"

When working with git, you will want to

(a)

You’ll need to pull your new repo. Move “first.tex” into your repo.

(b)

Type git add first.tex to stage the changes you’ve made to the first.tex file. Or do git add -u to add all updated files.

(c)

Type git commit -m "My first edit" to commit the staged changes. You can also just do: git commit