First you drain the oil. I think theres like 15 bolts that need to come out in order for it to drop. They are all around the perimeter of the pan. Get a new oil pan gasket(about $45). Take off the pan put the new one on along with the new gasket and then your done. Its realy easy.
Just tighten them evenly. Dont go tightening one side then doign the other. Do them all together. Its not that difficult. You should tighten all your bolts like that when there are more than a few of them holding something together.