Puñña, or merit making, means doing skillful actions--mental, verbal, or physical. There are ten ways of making merit: by giving, by being virtuous, by becoming calm and mindful through meditation, by being reverent, by being helpful, by sharing merits with others, by rejoicing in others' merits, by listening to the Dhamma, by teaching the Dhamma, and by correcting one's views.
Temple of the Tooth, Kandy, Sri Lanka