jesus christ, nearly everyone is still in bed mate, and you expect a tutorial and pics to be uploaded in under an hour since your first post?? good luck with that...
Now unless your dad has tyre levers, he will probably end up stabbing himself with the screwdriver he's using...
For starters, you need to take the valve stem out of the tube valve... which requires a valve stem removal tool... then you need to undo the nut holding the valve to the rim.
break the bead (where the tyre "sticks" to the rim) by standing on it...
Stand on one side of the tyre, so the bead slides in under the rim, and using TWO tyre levers, start levering the tyre off. stick two levers in between the bead and rim, and lever a section about 4-5 inches across, over the rim. wedge one lever under either the disc rotor or sprocket, depending on which way the tyre is laying on the ground. pull the second tyre lever out from between the bead and rim, and take a bite a little further around. you need to keep moving the second lever around the tyre until the bead is OUTSIDE the rim all the way round... pull tube out, put new one in, poke valve through valve hole, put valve nut on a couple of turns, pump a small amount of air into the tube, then pull the valve stem out.
putting the tyre back on the rim, just reverse the process with the tyre levers, or better still, a rubber mallet if you have one.. if not, go very carefully with the tyre levers, making sure you dont pinch the tube.
Once you've tried the above, and pinched the tube, thus requiring a new one, get your dad to take you into Ipswich, there's bound to be a tyre shop or mechanic in there...
costs maybe $15 to have a tube replaced in a bike wheel...
Unless you have valve stem tool, tyre levers and a rubber mallet, dont even attempt it, you'll just make a mess of it.