You need to pop 10,000 bubbles in endless mode. The achievement will immediately fire.
The most efficient way I found to do this was to set the icons to #2, i.e. people. The person icon is tall enough that by dragging diagonally down and left along the edge of the heads, you can pop three rows at a time. This means only five drags per 15x15 grid rather than eight drags with smaller icons that can only pop two rows at a time.