To sort bottles according to color and match three of the same color for collection, follow these steps:

1. Identify and Group Bottles by Color: Start by examining each bottle and grouping them based on their color. Place all the red bottles together, all the blue bottles together, and so on.

2. Match Three Bottles: Once you have grouped the bottles, pick up three bottles of the same color. Ensure that you are holding exactly three bottles of the same color at a time.

3. Place in Box: After you have matched three bottles of the same color, place them into a designated box. This box will be used to collect the matched sets.

4. Repeat the Process: Continue sorting through the remaining bottles, matching three of the same color, and placing them into the box until all bottles are sorted and collected.

5. Collection: Once the box is filled with the matched sets of bottles, it will be carried away for further processing or recycling.

By following these steps, you will efficiently sort and collect the bottles according to their color, ensuring that each set of three matching bottles is properly boxed and removed.