If not too many pills have been formed then they can usually be removed by hand. This should be done routinely after drying, or just prior to ironing.
A comb can be used to remove pills, but this should be done very gently and carefully so as to not damage the item of clothing which may lead to the formation of holes.
Small battery operated pill and lint removal devices known as either “de-pillers” or “fabric shavers” are low cost and generally very effective at removing pills and giving your clothing an as-new appearance again.
There are also a number of ways to avoid pilling.