So, in this example, the formatting would look like this:
{{Stub Category|article=[[Road]]s or [[Road Transport]]|newstub=Road-stub|category=Road transport}}
It is also advisable to add it to a larger stub category, if an appropriate one exists. For Category:Road stubs, no such category exists however.
In order to increase the category's effectiveness and visibility, it's generally advisable to add your category to several categories. For example, this would add it to the Roads category:
[[Category:Roads]]
When you are done, it is important that you make sure that the new stub and the new stub category are linked correctly to other categories. Using the road-stub as an example, the road-stub category needs to be a member of Category:Stub categories (because it's a stub category) and Category:Roads (because it's a category consisting of roads). If your new category has been made from part of an existing stub category or categories, these should also be listed here (so, for example, Category:France geography stubs should be part of Category:France stubs and Category:Europe geography stubs).
At this point, you should add the new stub category to this list: Wikipedia:WikiProject Stub sorting/Stub types
Once the new stub category is approved by the WP:WSS (which should normally be done before it is created), to make clear that it underwent the mandatory revision process and was approved by means of consensus, add the {{WPSS-cat}} template to the category page.
If you have doubts or comments regarding any part of the process, do not hesitate to address them here.