TA Challenge: Part 3 - Bollinger Bands: applications

In $RH PetroGas(T13.SG)$'s chart above, it entered into an uptrend when the price moved above the BBI on Feb 2022 and a long (buy) position is triggered. There was a Bollinger Band Squeeze which indicated a period of greater volatility (BBs expand) and the price surged. The price moved above the upper band which indicated a strong uptrend. Then in Mar 2022, there was a bearish engulfing candlestick which was a reversal signal. A short (sell) position was triggered.
The stock then moved downwards to the middle band. It fell below the BBI. However, there was a bullish engulfing candlestick the next day and a buy position was triggered. The long and short positions can be determined this way. The upper and lower bands may act as resistance and support levels.
Bollinger Bands and MACD

In $IFAST(AIY.SG)$'s chart above, the price surged strongly above the upper band to $10.10 and pullback to the middle band. It then made a second top in Oct 2021 and the price didn't rise above the upper band. A M-Top was formed and signalled a trend reversal to bearish. When the second top was formed, the MACD showed a lower top which indicated a bearish divergence. It confirmed the downtrend and the price fell below the support.
Examples

In $Rex Intl(5WH.SG)$'s chart above, the prices fell below the lower band in Nov 2021 and made a low of 0.26 and moved slightly above the middle band. It then made a second low without the price falling below the lower band. A W-Bottom was formed and signal a trend reversal to bullish. When the second low was formed, the MACD made a higher low which indicated a bullish divergence. This confirmed the uptrend and the price rose above the resistance.

In $Tritech(5G9.SG)$'s chart above, the price rose above the BBI in late Mar 2022 and triggered a long position. The price surged above the upper band and the bearish candlestick triggered a short position. The stock then consolidated. When the price tagged the BBI, another long position was triggered in mid Apr 2022.
Conclusion
Bollinger Bands is a momentum indicator which shows the volatility of stocks. They can be used to determine the strength of the trend, determine overbought and oversold levels, determine resistance and support levels, and for monitoring of breakouts and reversals. They can be used with other technical indicators for better results. The time period to use depends on the preference of the user.
This concludes the challenge. Don't forget Parts 1 and 2 in the link on top.