Five key points to note when confirming a "W" double bottom pattern:

1. Price movement

First, observe the stock price movement to confirm whether two bottoms have formed, connected by a relatively higher low point, creating a "W" shape.

2. Trading volume

Trading volume should gradually decrease during the formation of the bottoms, indicating weakening market activity, and then start to increase during the reversal, showing increased buying interest. This coordination strengthens the confirmation of the bottom.

3. Time span

The "W" pattern typically has a longer time span at the bottom, indicating that the market has undergone accumulation and consolidation. The length of this time span is also an important indicator for confirming the pattern.

4. Neckline breakout

Once the pattern is confirmed, investors can wait for the stock price to break through the neckline of the "W" pattern (a horizontal line connecting the two bottom highs) before buying, which is a common confirmation method.

5. Other technical indicators

In addition to the above points, investors can also use other technical indicators such as moving averages and the Relative Strength Index (RSI) to confirm the "W" pattern. The coordination of these indicators can improve the accuracy of pattern confirmation.