I am using jqGrid 3.5. Can I change the style and look of the grid and make it more beautiful using jQuery or custom CSS or something else?
One of the big features of jqGrid 3.5 is integration with jQuery UI Themes. You can build and/or select a theme from here. Then just add a reference to it in your page:
<link rel="stylesheet" type="text/css" href="../css/redmond/jquery-ui-1.7.2.custom.css"/>
This will get you a grid that looks very good, with a minimum of effort.
Does that solve your problem or do you need to overhaul the grid look-and-feel even more?