Changing the pads is pretty simple as on most vehicles now days. The things to watch out for are any prominent grooving of the rotor which will just get more pronounced if only the pads are changed and the rotors not turned to remove the grooves. Also if you are noticing any "pulsing" when you brake that feels like the brakes are grabbing and releasing, you should get the rotors turned at the same time you replace the pads or you are looking to get whiplash from the pulsing by the time the new pads wearout. Make sure you check to see that the old pads are approximately the same thickness both inside and out and on both sides of the vehicle. If they are not then you may have a caliper sticking and should have it serviced.
In short if your breaks are performing well now, then just be careful not to tear the rubber boot on the caliper and by all means don't buy the cheapest pads at the auto parts store (they always wear poorly and cause problems for me).
You forgot to compress the brake piston !!!!!!I just tried ...to replace my gf front pads on her trail blazer i took one bolt out and the caliper swung open..i then replaced the pads and the caliper wont swing shut now..it looks like with new pads plus rotor it is too thick to fit.. it is driving me crazy..2002 tblazer..plz help.. thanks