linking I phone to I pad.....

ok,, i hear this can be done...but i am pretty challenged when it comes to this stuff i just know the ipad is awesome to use easier than the i phone but.... i can get the internet on it...there is supposed to be a way of " tethering" them


could i get a "instructions for dummies" explaination please......

i know its a great fathers day gift....and my wife hasnt used the e-reader w/ light charger and hard case that i bought her...since i got the ipad....lol