Remove the "C" clip from the axle
Press the bearing and retainer and backing plate off the axle
Knock/press the four bolts off the backing plate that attaches the axle to the housing.
replace the four bolts/studs back into the bearing cup
Replace the seal/dust cover on the end of the bearing cup that goes towards the axle flange
Knock/Press the bearing and retainer on to the axle
Before installing axles, replace the axle seals in the housing, OEM are the best for seals.
Replace the "C" clip
You are done
I recommend that you replace the axle bearings at this time.
If you do not have a press or access to a press, here is another method of changing axle bearings
http://www.4x4wire.com/toyota/maintenance/rear_axle/wheel_bearing/Looks a little Primitive Pete, but it works.
I recommend that you change the axle housing seals before you install the axles, OEM seals are the best