updated template for updating citation information

Author: jspaaks

{{cookiecutter.project_name}}/.github/next_steps/04_citation.md

@@ -4,4 +4,58 @@ labels:
   - 'action required'
 ---
 
-Citation data instructions
+The repository has been set up with a [GitHub action](https://github.com/marketplace/actions/cffconvert) that monitors
+your citation data. It checks the following 6 aspects:
+
+1. Whether your repository includes a `CITATION.cff` file
+
+    _By including this file, authors of the software can receive credit for the work they put in._
+
+1. Whether your `CITATION.cff` is valid YAML
+
+    _Visit https://yamllint.com to see if the contents of your CITATION.cff are valid YAML._
+
+1. Whether your `CITATION.cff` adheres to the schema (as listed in the `CITATION.cff` file itself under key `cff-version`
+
+    _The Citation File Format schema can be found [here](https://github.com/citation-file-format/citation-file-format),
+    along with an explanation of all the keys. You're advised to use the latest available schema version._
+
+1. Whether your repository includes a `.zenodo.json` file.
+
+    _With this file, you can control what metadata should be associated with any future releases of your software on
+    Zenodo: things like the author names, along with their affiliations and their ORCIDs, the license under which the
+    software has been released, as well as the name of your software and a short description. If your repository doesn't
+    have a .zenodo.json file, Zenodo will take a somewhat crude guess to assign these metadata.
+
+    The `cffconvert` GitHub action will tell you what it expects to find in `.zenodo.json`, just copy and paste it to a
+    new file named `.zenodo.json`. The suggested text ignores CITATION.cff's `version`, `commit`, and `date-released`.
+    `cffconvert` considers these keys `suspect` in the sense that they are often out of date, and there is little
+    purpose to telling Zenodo about these properties: Zenodo already knows._
+
+1. Whether `.zenodo.json` is valid JSON
+
+    _Currently unimplemented, but you can check for yourself on [https://jsonlint.com/](https://jsonlint.com/)._ 
+
+1. Whether `CITATION.cff` and `.zenodo.json` contain equivalent data
+
+    _This final check verifies that the two files are in sync. The check ignores CITATION.cff's `version`, `commit`, and
+    `date-released`._
+
+
+It is likely that your `CITATION.cff` currently doesn't pass validation. The error messages you get from cffconvert are
+unfortunately a bit cryptic, but doing the following likely helps:
+
+- [ ] Fill in your given name for `given-name`
+- [ ] Check if the `family-name` key needs updating. If your last name has a name particle like `von` or `van` or `de`, use
+  the `name-particle` key; if your name has a suffix like `Sr` or `IV`, use name-suffix. For details, refer to the
+  schema description: https://github.com/citation-file-format/citation-file-format
+- [ ] Update the value of the `orcid` key. If you do not have an orcid yet, you can get one here
+  [https://orcid.org/](https://orcid.org/).
+- [ ] Update `date-released` using the YYYY-MM-DD format
+- [ ] Update the `doi` key with the conceptDOI for your repository (see [https://help.zenodo.org](https://help.zenodo.org/)
+  for more information on what a conceptDOI is). If your project doesn't have a DOI yet, you can use the string `10.0000/FIXME`
+  to pass validation.
+- [ ] Update the `keywords` array with some keywords of your own that describe your project
+
+Once you do all the steps above, the `cffconvert` workflow will tell you what content it expected to see in
+`.zenodo.json`. Copy-paste from the GitHub Action log into a new file `.zenodo.json`.