how to wipe my data and make os x like new for a return?

[jesusplay]

I'm going to return a rMB I just got yesterday and the last time I did this with a mac I wiped the hard drive and took it to the store. When they turned it on it was a black screen with an indicator in the middle or something.

They were trying to figure out what I did, I know I wiped the hard drive, but I guess I also wiped out the OS X?

I was really confused, and they didn't know what I did and it was a headache.

I just want to make the OS like day one with no trace of any of my data.

 

[The Economist]

I'm going to return a rMB I just got yesterday and the last time I did this with a mac I wiped the hard drive and took it to the store. When they turned it on it was a black screen with an indicator in the middle or something.

They were trying to figure out what I did, I know I wiped the hard drive, but I guess I also wiped out the OS X?

I was really confused, and they didn't know what I did and it was a headache.

I just want to make the OS like day one with no trace of any of my data.

Follow these instructions. Also, read this first.

Please, read them carefully.

PS: You must be connected to the Internet to reinstall OS X as it will download the OS

 

[DeltaMac]

I would add to that:
After erasing the drive, then reinstalling OS X, you can quit (command-Q) when it first asks you for your personal info, such as an AppleID. You don't need to set the system up, just reinstall OS X.

Or, even better, if you simply returning your new MB, you can just erase the drive, and leave it that way.
This time, no confusion, you will know exactly what you did (Erased the hard drive, and left it blank.) That way, you don't need to waste your time downloading the system, when you are just returning the MB to the store....