Hi Valentin,

The following link will get you on your way:

https://our.umbraco.org/documentation/getting-started/backoffice/property-editors/built-in-property-editors/grid-layout/settings-and-styles

However, here's an example using the default grid view:

1. Login to Umbraco and go to Developer -> Data Types.
2. Find your grid data type in the Data Types folder.
3. Click the your grid data type and scroll down to Settings in the main pane.
4. Click Edit
5. The right sidebar that opens up allows you to set up your row and column settings.

Here's one to get you started:

[
  {
    "label": "Background Colour",
    "description": "Choose a background colour.",
    "key": "class",
    "view": "radiobuttonlist",
    "modifier": "col--{0}",
    "applyTo": "cell",
    "prevalues": [
      {
        "label": "White",
        "value": "white"
      },
      {
        "label": "Green",
        "value": "green"
      }
    ]
  }
]

The options here are all listed in the documentation link above.

Hope that helps.