Binder exercise: many participants struggled with pushing files to GitHub

[bast]

We need explicit steps here and this seems not enough:

"Create a new GitHub repository.

Commit and push the notebook which we have created earlier to this repository"

[MatiasJJ]

Could be a preparation step (I think some lessons have such in a separate box) that describes:

• you need a github repo. Make a new one or open an existing one.
• you need a jupyter notebook in the repository. Make a new one or use an existing one, (or download that linked there)
• create requirements.txt -instructions here rather
• commit and push

then starts the exercise instructions

[MatiasJJ]

I have time to do this maybe Tue evening 😬