Just did mine this weekend I'm not a mechanic but have done a lot of this. I have done brakes on 3 or 4 other cars I've owned. Swapping the pads on the Sedona was easy if you've done brakes before
I totally agree with the comments above get experienced help for at least your first job.
Identifying the correct pads for teh Sedona was not easy see below.
Tales of caution and over confident youth.
My first experience of working on brakes was in my early twentys, working on the street in central London....very hard to test brakes without driving a car so that left me in rush hour traffic with in fact no brakes! and just a handbrake! Quite a scarey adrenaline shot for me and my helper, there we were cruising a one way system in traffic desperatley looking for an opportunity to crash slowly and safely into a kerb.... we made it just... but thank God no child ran into the road.
Our mistakes were that despite our best endevour bleeding the system for ages ....it wasn't in fact bled fully and had a nice giant spongy air bubble in it rendering brakes nonexistent!
(By the way you can TOTALLY forget ever trying to stop a Sedona with the handbrake its so heavy you'd have more luck stopping it like kids do on a bike, opening the door and putting your foot on the tarmac .....Thats a joke don't do it -you'll break your leg and run yourself over)
pad sizes complications
The local Motor Factors were very helpful, on the phone they had 3 different pad styles quoted and available for my model sedona , so I removed photographed and measured the old pads, installed those back on the car and drove down to see the factors. Even with the photos and measurements of the old pads, 2 of the models available were so similar I had to buy both . Even then with the old pads and the 2 new models (same brand) side by side it took me 20 minutes of measuring every feature to figure out where the significant definite observable difference was. The length is spec'd as 0.4mm difference but your really wasting your time trying to measure that difference off an old rusty pad.
Finally at the centre of the "arch" in the pad I measured a 2/3 mm difference in the height of the two models and therefore was able to match to the ones in the car.
Anyway all well ,apart from my usual issue 3 point turning the car brakeless so you can do the other side safely...yikes...
(I'd recommend every driver to find somewhere safe and drive a car that has no brakes...just at 2 miles an hour. till you do this you just don't realise how scarely dangerous it is. )
As a DIY er here's the obvious tips
get someone who HAS DONE IT BEFORE to help you
Chock the wheels
I never go under a car on one jack. I always jack with 2 decent jacks and an axel stand just in case. I had an old car jacked once where the chassis gave way on the jack and down the car came.
So my two jacks are positioned to do the same lift one fails the other will hold the car without a change in position.
If you are at all unsure Photograpgh on a digi camera before and during your dismantle, this was a live saver when I did brakes on an Espace (the parts supplied to me were correct, but they had been assembled slightly wrongly into the box at the factory, checking through the photos of the ones on the car proved this beyond doubt and allowed me to reassemble.)
Always double check every step.
Always doublecheck every step
Never break off half way through, I just forget where I am in the process.
Always ensure you get the pads on the disks before you very carefully set out for a test drive. Keep your distance for the first mileage and go back and check all your nuts are tight after you've done a few miles I like to keep testing the brakes , for safety and for the satisfaction.
Anyway pads done for around £30 (refunded on the ones didn't use) and the Sedona seems fine .
Get help and be safe.