I run a SR4 game where, after a few missions, with a character not starting out as a hacker, a player decided he wanted to develop in that direction. As neither of us knew the matrix rules well, i decided to design a few matrix tasks for him, from the easy "you have to monitor the communication of a person on site for a few hours" to the hard "you have to hack into a node, look for data, copy it, edit it, then leave without trace, in a given amount of combat turns (with extra difficulties)", then i sent it to him in e-mail. He had to look up the rules, and compose an action-to-action report on what he is doing for each task. I only let him develop into a hacker after he understood how he had to approach these tasks.
It was a great excercise for both of us, and we learned much from the process. If you are in the lucky position of already knowing matrix rules, so much the better. And sending the tasks in e-mail, he has time to browse the rulebooks, and is not embarrassing at all, as the others don't even need to know about it. And if he can't or doesn't want to solve these tasks in some time, then there really isn't much to do, and he has to leave decking to one who has the understanding or the will to learn.