When the price touches the support trend line, or the lower trend line, of an ascending channel, a buy trade is signaled. When the price touches the resistance trend line, or the upper trend line, a short trade is signaled. It is also important to pay attention to the volume of the stock. If the stock breaks support with high volume, it is a greater indication that the trend is broken. However, if the stock breaks support with low volume, it is okay to hold a little longer since it could be a false breakout. If you choose to hold a little longer, make sure you have a stop loss.