How to change slider text on theme and theme background image

HOw do i insert my own slider images and my own text own the slider? How to change the theme background image also?

To add your own text to the slider you have to fill the text field "Content" on page ThemeSettings --> Slider in the dashboard.
The background of a theme can be set by different ways. To change it you have to edit the file style.css.

I went on theme settings and slider dashboard and text didn't change on it and what lines do i change on stlye.css to put the slider images and what's the maximum of slider images allowed on template?