How do I install maverick os x without back up files?

Question

I have just bought my daughter a second hand macbook air for school,
whilst trying to restore it back to factory settings to reinstall maverick os x, it asks for a apple id and password.
I have put my id and password in and it wont install.
This is our first experience with a mac, and so far not enjoying it.
Any help would be greatly appreciated.

Answer 1

Oh, duh! Missed where you noted above it's a 2013 MacBook Air.
Okay, that Mac shipped with Mountain Lion, 10.8.x. Whether you try a Recovery Mode restart, or an Internet Recovery Mode restart, the Mac will want to install the same OS that is in the hidden recovery partition of the hard drive. So it will try to reinstall Mavericks every time. To stop it from doing that, you need to wipe the entire drive.
Startup, or restart the Mac and immediately hold down the Command+Option+R keys to boot into Internet Recovery Mode. Note: it's better to use a wired Ethernet connection to your cable or DSL modem rather than wireless for this.
You will get what looks the same as a normal recovery mode restart, except you're working off the firmware rather than the hidden recovery partition. You need to do this so Disk Utility can wipe the drive since you can't remove the startup partition out from under yourself.
Launch Disk Utility and select the physical drive name in the left pane.
With the physical drive selected, click on the Partition tab to the right. Where the graphical display of the current drive layout says Current…
…change it to anything other than Current. If the drive is one partition for the whole thing, and that's what you want, then choose 1 Partition from the drop down menu. Note that the hidden partition is not shown in this display unless you turn Disk Utility's debug menus on (you can't do this in Recovery Mode). It is there, and that's what you need to get rid of by repartitioning it.
I'm going to assume one partition as your choice. After changing the menu to 1 Partition, give the drive any name you want in that field. Click the Options button to make sure the radio button choice is GUID (it already should be). The format should also default to Mac OS Extended (Journaled). Click Apply. It will take just 10 seconds or so to repartition the drive.
Quit Disk Utility to get back to the main menu and choose to reinstall OS X. With no reference for any other OS on the drive, the Mac will reinstall the original OS it came with from Apple's servers, which will be Mountain Lion. It will also recreate a new hidden recovery partition to match the OS level it installs.
Once it's done and the Mac restarts to the newly reinstalled OS, you can either apply any updates available for Mountain Lion and leave it at that OS, or you can create your own App Store account and then "purchase" and install Yosemite, 10.10.x.