First you want to do is remove that dust cap. There are special pliers you can get to do this so you don't end up denting and mangling the cap. If you're careful with vise-grips and a rag, it may work. Inside the hub there will be a large nut, probably two, one would be a castle nut (this is where specifics get hazy, sorry- but they're all generally alike) with a cotter pin through it. Remove these nuts/whatever method is used to prevent the outermost nut from spinning free. Keep everything in the order that you removed them.
There should be a washer after that, or a few, usually with a tang which fits into the key-way on the spindle shaft. That's so you know which way it goes back on, remember the orientation of the washers. Then there should be the outer bearing to remove. Just pull it out, no tools needed. You should now be able to pull the hub/rotor assembly off the spindle- keep in mind the inner bearing (on the backside of the hub) will be free now and could fall out at any moment. If it hits the ground, it's garbage. Period. Be careful and put it on a clean surface. The inner bearing race will, again, stay in the hub.
You can now remove the rotor via the bolts. One trick is to bolt the hub back onto a wheel and use the wheel flat on the ground to help you hold the hub while you're levering off the bolts.
Just keep everything in sequence of removal, and clean. Push some new bearing grease into the wheel bearings while they're off. Literally, you just take a handful of grease and push it with your palm through the bearing cage until it comes out the other side.
De-grease the rotors with alcohol as well, or brake cleaner prior to fitment of the calipers. I don't know the specific torque that the spindle nuts go on at; hopefully someone else will chime in if I don't look it up. Tighten to this torque and then backoff the nut 1/3 of a turn to set the proper preload and avoid burning up a bearing.