Category talk:Transport in Saint-Martin (France)

I tried my best to understand how to simply add (sub), (sub/sub) ... up to ... (sub/sub/sub/sub) categories, but I failed !
I had read all the Help pages ... All what "I should not do", but I just did not find simple instructions to quickly create a categories tree.
I may be brainless ... also please Help !
Don't try to explain me, but just do the job and create here the following sub/categories tree :

1. Roads on ...
   1. Main roads on ...
   2. Secondary roads on ...
   3. Amazing things on roads of ...
   4. Accidents on roads of ...
2. Bridges on ...
3. Roundabouts on ...
4. Ports of ...
5. Public transportation on ...
6. L'Espérance Airport on ...
7. Ways of life in ...

Many thanks ... and a big kiss, --Millot (talk) 11:00, 17 April 2012 (UTC)