Cheat Sheet:

TO CENTER STUFF:

HTML: 
<center> </center>

CSS: 
text-align: center; 

HTML: 
<b> </b>
<strong> </strong>

CSS: 
font-weight: bold; 

(if you're font comes in different weight you can use that instead:
font-weight: 700;)

HTML: 
<i> </i>

CSS: 
font-style: italic; 

HTML: 
<u> </u>

CSS: 
text-decoration: underline; 

HTML: 
<strike> </strike>

CSS: 
text-decoration: line-through;

HTML: 
<big> </big>

CSS: 
font-size: larger;

HTML: 
<font color="#ff0000"> </font>
<font face="arial"> </font>

CSS: 
font-family: Arial, Helvetica, sans-serif;
color: #ff000; 

<img src="DIRECT-IMAGE-URL" alt="Descriptive Text">

<a href="URL"> </a>