Added style guide stub page and referenced it

modules/contributor/nav.adoc

@@ -4,5 +4,6 @@
 ** xref:development_dashboard.adoc[]
 ** xref:service_discovery.adoc[]
 ** xref:opa_configuration.adoc[]
+** xref:style_guide.adoc[]
 
 include::partial$adr-nav.adoc[]

modules/contributor/pages/steps.adoc

@@ -56,7 +56,7 @@ helm install <operator> deploy/helm/<operator>/
 
 1. The Stackable Platform documentation can be found at https://docs.stackable.tech/. The documentation is built with Antora from the sources in the https://github.com/stackabletech/documentation[documentation repository] and the `docs` directories in the operator repositories. Follow the steps in <<Preparation>> to be able to change the documentation.
 2. Make your changes.
-3. Create the documentation locally to ensure that the formatting is fine and all links are specified correctly. See the https://github.com/stackabletech/documentation/blob/main/README.adoc[`README.adoc`] file for further details.
+3. Create the documentation locally to ensure that the formatting is fine and all links are specified correctly. See the https://github.com/stackabletech/documentation/blob/main/README.adoc[`README.adoc`] file for further details and the xref:style_guide.adoc[] for style and formatting guidelines.
 
 == Changes in the operator-templating
 

modules/contributor/pages/style_guide.adoc

@@ -0,0 +1,14 @@
+# Documentation style guide
+
+// make this document a whole "How to contribute documentation" (?)
+// just a style guide?
+// should we document also stuff about the structure?
+// what about graphics?
+
+// graphics and a whole "How to contribute docs" is not in the scope
+// probably not to be done for now (even though it would be nice to have)
+// it sucks a bit to have the style guide a bit in a vacuum, but I think for now it would be fine. I could make a ticket for writing "How to contribute docs"
+
+For consistency and clarity, we provide some guidelines on how to write documentation.
+
+We follow the link:https://kubernetes.io/docs/contribute/style/style-guide/[Kubernetes documentation style guide] and the link:https://developers.google.com/style/[Google developer documentation style guide].