See my previous answer on this
Preventing postback[
^]
You can 'prevent postback' so the buttons do not call back to the server.
If that's what you want, you'll need to run some sort of client side functionality to do something when you click the button, normally some javascript.
Otherwise, if you want server side code to run, just ignore the postbacks in your Page_Load event - you can write code like
if (!Page.IsPostBack)
{
}
Then, just create event handlers for your buttons and write code accordingly.
What approach you should use depends entirely on what you're trying to achieve