With an external style sheet, you will be able to effect your entire website with just one file. First you need to create a CSS file. Then in your HTML file, you must include a reference to the CSS file inside of the <link> element.
Example: <head><link rel="stylesheet" href="mystyle.css"><head>
With an internal style command, you will be able to effect only one webpage on your website. They need to be entered inside of a <style> element inside of the head section.
Example: <style>body {background-color: linen;}h1 {color: maroon;margin-left: 40px;}</style>
With an inline style command, you will be able to effect only one element. In order for an inline style to take effect, you must insert your style commands inside of the HTML element you wish to change.
Example: <h1 style="color:blue;text-align:center;">This is a heading</h1>
Create a CSS file and add the styling rules as followed:
/* styles.css */
p {
color: red;
}
Then link the CSS file in the <head> section in your HTML document as listed below:
<head>
<link rel="stylesheet" type="text/css" href="styles.css">
</head>