Heading Size
For the title you will choose the heading size of 1 (h1) and for the subtitle you will choose the heading size 2 (h2). Between the body tags <BODY> and </BODY>

you will type the following text:
<h1 align=center >Name of Your Business</h1>
<h2 align=center >A Subheading That States Something About Your Business</h2>
Example company is shown below:

Result shown below:
Olives Are Us
Homemade Quality Olive Products Made by All Of Us at olivesareus.com
FYI: HTML codes are not case sensitive. For example <H1> and <h1> are the same.