Creating custom forms from the list settings page is the most direct and recommended route when creating custom list forms in SharePoint Designer 2010. To create a custom form for the out-of-the-box Announcements list, perform the following steps.
The following assumes that you have either an existing Team Site with a default Announcements list or that you have created a new Announcements list, which is based on the default Announcement list template.
1. With your site open in SharePoint Designer, click Lists and Libraries in the left-hand navigation pane.
2. In the available lists and libraries list, click Announcements to open the Announcements settings page.
3. On the Announcements ...