Hi, i am a web designer. Skills is mostly HTML, CSS. For wordpress normally i will buy the the themes and build up from there. How do i go about not buying a theme but instead create on my own, what skills do i need to do this ? PHP ? Thanks
PHP. The structure of a theme is easy, there are good tutorials all over the internet if you really want to learn. It's good to know, and then build your own basic framework to use so you don't have to recreate the theme files every time you make a new one. Another option is to use something like the blankslate theme or a blank Bootstrap theme, and build from there.
HTML, CSS, and minimal PHP is what you need to know to create Wordpress themes. Start by reviewing the official documentation: http://codex.wordpress.org/Theme_Development http://codex.wordpress.org/Theme_Customization_API