Foren / Cotonti / Support / How to Make new Theme

Hi everyone,

I am still using seditio old version. I converted my database to cotonti siena what was important for me. Then I want to make new theme for my website.

I prepared my HTML files. First I was thinking I can use nemesis theme for reference theme but for example there is no forum tpl files in the folder. Then I found tpl files on the modules/forums but I also found tpl files (forum) on the symisun-03 theme folder. So I am confused now How I can start to make new theme ? Someone can guide me?  I also need clean and well coded theme for reference.

Thanks a lot.