Never sand with bare hands, your fingers simply cannot provide the even pressure to make an area smooth. The small disks you describe are for higher speed leveling, but can get you in trouble quickly. Used wisely they can get you in the ballpark, then finish with a hand block. If the area is flat, use the hard block like Brandon suggested. Change your paper often, worn paper does more bad than good. Your repair area should be built up, then get knocked down to smooth without cutting too much of the original surface. If the area has a curve, use a 3m #20 (p/n 05526)pad, great for wet or dry sanding. Most places also carry the sanding sponges that can work well on a budget.
