Sorry if the following sounds a bit crude, but it is a simple case of identifying the male flowers from the females. The females have a little tiny bud or baby melon at their base and the males have nothing.
On a nice dry morning just as the flowers open in the sun, take a male flower, strip back its petals carefully and brush its pollen - you'll see what looks like yellow dust at the end of little stalks(stamens,I think they're called) into the stigma of the female flower. You can pollinate more than one female flower at a time with a male flower. When finished, discard and pick another male flower to repeat the process on the other female flowers. Gently does it. If the pollination is successful, you will see a slight swelling at the base of the female flower within a short time and thus a melon grows on.
if you plant enough melon plants, there will be enough flowers to go around.
I would find this method easier than using a soft paintbrush or relying on insects.
I hope that describes it to you and good luck!