NEWBIE - Return To Stock Mac

[towersarielle]

Hi, I am a huge newbie. I don't know any technical terms or anything like that. I don't even know if I am posting this in the correct place. I'm not educated on forum etiquette. But I need some help ASAP. I need to return my HTC Evo 4G LTE back to stock as soon as I can. I have to return it back to Sprint. I did a Full Unroot through my Super SU app but I still have Clockwork Mod Recovery on it. I need to get that removed and have the little sign that says *Tampered* removed from Boot Loader. Any really dumbed down help that can be provided would really be helpful. Thanks.