Question: I am new to nopCommerce and trying to make HTML to theme on it I googled lots of things but not able to get proper way to create customized theme nopCommerce, can any one help,

Thanks in advance

Answer: 
The easiest way:

1. Copy the folder at `~/Themes/DarkOrange` to `~/Themes/YOUR_THEME`. Modify the corresponding items in theme.config.
2. If you need to change any view, copy that view from `~/Views/SUB_FOLDER/FILE_NAME.cshtml` and paste it under `~/Themes/YOUR_THEME/SUB_FOLDER/FILE_NAME.cshtml`.

For example, if you want to change the code in `~/Views/Shared/_ColumnsOne.cshtml`, copy that file and paste it under `~/Themes/YOUR_THEME/Shared/_ColumnsOne.cshtml`.
3. If you do not need to change any view, then modifying `~/Themes/YOUR_THEME/Content/styles.css` is enough. (Also make sure you update `~/Themes/YOUR_THEME/Views/Shared/Head.cshtml` to point to your CSS)

**Rule of Thumb:** nopCommerce will look for the specific view in your theme. If it can't find the view then it falls back to the original views at `~/Views`. Otherwise your theme's views override the original views.
Copy all the files inside `~/Views` to your Themes: `~/Themes/YourTheme/Views`

Then just modify any `.cshtml` file inside.

I hope it helps!