It doesn't require a programmer or designer (I'm neither one either) - just someone that is familiar with their software that they use.
Use the provided code in your EXTRA.css with standard CSS font-size:YYpx, where YY is the numeric amount you want the size.
Code:
.node .subForumList li .nodeTitle a:link {
font-size:40px;
}
.node .subForumList li .nodeTitle a:visited {
font-size:20px;
}
would be an example. You (of course) would need to adjust the font sizes.
Some stuff can be controlled via the style properties in the ACP, but not everything.