Small quantities can simply be rubbed off with a soft glove, though you will have to be diligent and sharp-eyed for a year to be certain of getting rid of them. Larger amounts will need spraying with insecticide. I have had the best luck with a mixture of carbaryl and a surfactant, sprayed thoroughly, three times, two weeks apart. A systemic such as imidacloprid also works, and needs little or no mixing, but it is slower and less certain.