You need to tell us what model laptop you have so we can help you locate the information you seek.
I did search for generic recovery information and found this link on the Gateway site. Scoll down the page and there are files (pdf) you can download under the Restoration Guides heading.
Ok...
Now all you have to do is reference the link I posted and look for your laptop. Your laptop is listed and the documentation you need is posted for it. Good luck!