How to begin on redesigning the forums

[VisualizeEdits]

I've been working nonstop the last couple days developing the headers and everything other than the forum itself. Now that I can start working on the forum, I'm not sure how or where to begin. :/ 

The problem is the the forums consists of many tables that could ruin my plans for my design, so would it be possible to turn the forums into divs? Does the forums really need to rely on tables to run properly? (If so, which templates do I begin on (the index for start).

I'm not asking anyone how to code this, but just looking for direction in making my design work without interfering with major codes to make the forum itself work properly.

Maybe I should start a new theme (just for the forum) to work on the forum design until I've fully finished it, then transfer it to my official theme?

Here's my planned design for the forums.
https://gyazo.com/86af72a26afacb2872fa822b5dcb1781

The website: http://LSGForums.com/

[WallBB]

You need to modify all tables to div, you should start with forumbit templates and than forumdisplay.
There are a lot of templates that you need to modify though.
Good luck