Hide Update button on first page

I am entering some details in my form and i want to save and display it in a gridview, which is being done. Now when i click on edit button i want to go back on the form page and show an update button.

The problem is the button is visible also at the starting when i enter data for the first time. Pls help me where do i enter the visibility option in my application.

Thankx in advance...