1. Open the "Sort Them Bubbles" game on your mobile device.

2. You will see several tubes filled with colorful bubbles, each tube holding a mix of different colors.

3. Tap on a tube to pick the topmost bubble.

4. Tap on another tube to place the picked bubble on top, but only if the top bubble in that tube is the same color or if the tube is empty.

5. Continue tapping and transferring bubbles one at a time to stack them by color.

6. Each bubble can only be moved on top of a bubble of the same color or into an empty tube.

7. The goal is to sort all the bubbles so that each tube contains only bubbles of a single color.

8. You can only move one bubble at a time, so plan your moves carefully to avoid getting stuck.

9. If you find yourself unable to make any more valid moves, use the "Skip Level" button to move on to the next puzzle.

10. Watch for increasingly challenging levels that require more strategic thinking and planning.

11. Enjoy the relaxing gameplay, colorful visuals, and satisfying feeling of solving each puzzle.

12. Keep playing to train your brain and master each level with fewer moves.