If would be MUCH more helpful if your site was online – as we could help you with specific recommendations for your site/logo, however . . .
Assuming you are working with the J3.x/T3v2 version of JA Zite . . . .
If you haven’t yet done so, create a new file called “custom.css” within file path –> /templates/ja_zite/css/
Within that custom.css file, paste the following CSS rule:
h1.logo a {
background: url("../templates/ja_zite/images/logo.png") no-repeat scroll left top rgba(0, 0, 0, 0);
display: block;
height: 180px;
width: 93px;
}
You can modify the above CSS rule with your own logo image and adjust the height/width properties to fit your logo dimensions.