SharePoint 2007 - Add a Custom Web Part to your Site

In your Home Page, click on Site Action and select Site Settings.

Under Galleries click on Web Part. Click the New button. Now find your Custom Web Part, check the box next to it, then click on the Populate Gallery button at the top of the page.

Now you can add the Web Part to your home page. Got back to your page at http://myserver/sites/myfirstsite. Click Site Actions and select Edit Page.

Click 'Add a Web Part' on the left. You should now see your Custom Web Part in the list. Check this item and click the Add button.