We're talking brakes here... I would strongly suggest you have someone that knows what they're doing be involved whether you just watch, assist or he assists you. AFTER having seen it done it is not difficult but something I would not suggest doing on your own if you haven't before.
If I may reiterate your suggestion, have a friend with you who knows how to do it so that you won't mess up anything. The job might be "simple" for those who know how to do it. However, imagine what will happen if you lose your brakes.
Another is let the mechanic accompany you as you do it, if he's willing and then pay his professional fee.