How to make the header of gridview to make visible when we scroll through the records of gridview?

As I understand you need a scrollable GridView control with fixed headers. If this is what you want I suggest you go through these links:
http://weblogs.asp.net/dwahlin/archive/2007/07/31/freeze-asp-net-gridview-headers-by-creating-client-side-extenders.aspx[^]
Scrollable Gridview with Freeze header and sort image.[^]

There are plenty of similar articles on net if you try Google.

Hope that helps!