I just used one glass beads for each heart. The child uses his hand to grab each bead and place it onto the wooden tray then he puts the bead back on the heart tray one for in each heart.
For a variation of this you can use tweezers, spoon, thongs, or chopsticks. Also you can replaces the glass beads with smaller beads, or red colored rice and use a small container to hold the beads or rice. You can use water and a table spoon for spooning. Make sure you have a cloth towel so the child can clean afterwards.