Get a starter box and put together two decks. I would say Criminals and Haas Bioroid would be a good idea.
Play a "staged game" where the decks have been pre stacked to provide situations that gradually teach the core rules.
Let the runners first hand have some money making as well as an ice breaker and some cool hardware. Set up your corp deck to have som easy ice at first and an agenda and a upgrade.
Walk your friend through his first few runs at your central servers without an ice breaker. Then put some ice out and let him run into that. Then walk him through getting an icebreaker out that will get him through that ice.
Next build a modest server with some ice protection an agenda. let the hacker know what ice is in the server and what he will need to get through it. If you stacked the deck well he should have one of each ice breaker in a few turns.
After a few turns of walking the runner through your ice and showing the hazards of ice, start a new server and keep the ice face down and see if your runner friend makes the right decisions when running that server.
By now the runner should have a rough idea of what is going on and the rules of the game will fall into place from there. Just remember to keep everything open for your friend, show him each card your playing and ask to see his cards when he gets new ones so you can explain what he could do with all his cool stuff.
After a few games as runner have one friend sit with you as you play corporation together with either another new runner player or a fellow veteran player.
Last but not least, the first few games should be learning experiences for your friends so don't play to win. Play to teach and if they are into the setting, take time to chat about the art or the fluff text. Get into the game world and your friends will be hooked.
Sorry for wall of text, but I hope this helps. I bring new players in every weekend at my Netrunner game nights and after one game like this they are almost always hooked and getting a starter box of their own.