Well, that terrible ._. . If I was an alien, I would became friends with earthlings 
i would to but if i were under orders to destroy earth there are much more efficient means of victory then invasion, i was just stating a few of them. and if i became friends with earth i would not give them technology. we'd most likely just make weapons out of it and kill ourselves with them. so id just sit there, watching them. and put giant jumbotrons in the sky with giant speakers placed so they can be seen from anywhere on earth. that just runs an infinite loop of this
http://www.youtube.com/watch?v=wyguBEc2dw4that or say i give them new technology and give them a computer that is really windows '98 computer in a high-tech looking case, make it look desktop look advanced and high tech, and set the language to ancient egyptian hieroglyphs or something.
then when they find out what i did i play this on the giant jumbotrons
http://www.youtube.com/watch?v=dQw4w9WgXcQso yea, id do stuff like that
i would however reward good people with various rewards of amazing experience like a trip to a nebula or to watch a nutron star form, i would not give an object because then the gov could take it and make it a weapon, and because experiences are more valuable then objects i think. id however give furries the ability to become anthro if they so desire.