Upgrade apple iPad to ios6

This link explains some of the issues with upgrading iPads to newer version of the iOS ...

http://ipad.about.com/od/iPad-FAQ/f/Why-Cant-I-Upgrade-To-iOS-6-0-On-My-iPad.htm

I’m happy to assist further over the phone at https://www.6ya.com/expert/ronald_f3c54257e2cc2559

You cannot. The first generation ipad cannot be upgraded past IOS5. You will need new hardware to take advantage of the newer IOS6.

What's your model? Processor is bigger question.

Do you mean upgrade or downgrade ? Because the common version of iOS is now 7.
Maybe this will answer your question:
https://discussions.apple.com/message/19656311

on a 1.gen. pad it is impossible to install iOS6:
this model supports only iOS 5 !
- NO iOS 6/7/8
- the processor is too slow....
For the iPad first generation (A1219) before iOS 5 to update is only possible with connecting the device to iTunes on a computer. Plug it into your computer and open up itunes under devices click on your ipad and then click on check for update.
- but this model supports only iOS 5

depends on the model of your iPad:
For the iPad first generation (A1219) to update is only possible with connecting the device to iTunes on a computer.
- but this model supports only iOS 5
- NO iOS 6/7/8
--------------------
for all other models:
There are two ways to upgrade the iOS version of your iPhone, iPad, or iPod Touch - via connecting the device to iTunes on a computer
- or directly from within the device, but only since iOS 5, it is possible to upgrade the iOS version without the need to connect the iOS device to a computer (over-the-air update)
just go to: settings - general - software update

depends on the model of your iPad:
For the iPad first generation (A1219) to update is only possible with connecting the device to iTunes on a computer.
- but this model supports only iOS 5 - NO iOS 6/7/8
-------------------------------------------------------------------------------
for all other models:
There are two ways to upgrade the iOS version of your iPhone, iPad, or iPod Touch - via connecting the device to iTunes on a computer
- or directly from within the device, but only snce iOS 5, it is possible to upgrade the iOS version without the need to connect the iOS device to a computer (over-the-air update)
just go to: settings - general - software update

1st gen iPad are stuck at iOS 4 keep a good archive of your apps, you won't be able to replace them easily

Plug your iPad 2 into the device where you run iTunes. In iTunes, select the iPad in the left column, then select the Summary panel. At the upper right, continue by downloading and installing the latest version of iOS that will run on that device. We use iOS 7 on our iPad 2 - and it runs very nicely.

For the iPad first generation (A1219) to update is only possible with connecting the device to iTunes on a computer.
- this model supports only iOS 5 - NO iOS 6/7/8