To Customize WordPress Theme follow your style, you only need basic knowledge about CSS, javascript, php. The WordPress offers a editor to help you easy customize your theme.
In this article, I will show how to use this tool to customize wordpress theme.
Introduce
WordPress theme is a collection of templates and style sheets used to define the appearance and display of a WordPress powered website.
You can be changed, managed, and added from the WordPress admin area under Appearance » Themes. There are several free and paid WordPress Theme is available
Step by step to Customize WordPress Theme
These are steps to customize WordPress Theme which I applied for theme of this page.
Step1: Log in WordPress Admin Page
Step2: Go to Appearance > Select Editor
Step3: Select the CSS file which you want modify.
Step4: After you finish modify, press Update File button to save file.
This is my theme before customize:
This is my theme after customize: