A word of warning though, Any Apps you downloaded with your Apple ID will still require it to be Updated. So your mother will be asked for it when she tries to update the apps. That can get very confusing. Its better if you clear everything off, and start from scratch, so that your mother can have a clean iPad.
Getting to the langauge change is not difficult if you follow the steps even when you don't know what the options say.
The location of the Language change is still the same regarldess of what language it is in.
You can try to do it yourself while its in english, and wirte down the locations of the things you need to tap to get to them, or follow this guide. It will walk you through the change even if you don't undertsand the language.
Language Change:
Tap on the Settings icon.
Tap on the 6th option from the top. It should be General.
Scroll al the way to the bottom, and tap on the 3rd option from the bottom. That shoud be International.
Tap the first option: Should be Language.
Look for English in the List. Tap it and then Tap the blue button on the top right corner.
That should change the iPad language to English.