Scalpers use technical analysis but within this style, can be either discretionary or system traders. Discretionary scalpers will make each trading decision in real time (albeit very quickly), whereas system scalpers follow a scalping system without making any individual trading decisions. Scalpers primarily use the market's prices to make their trading decisions, but some scalpers also use one or more technical indicators, such as moving averages, channel bands, and other chart patterns.
When it comes time to take profits, the swing trader will want to exit the trade as close as possible to the upper or lower channel line without being overly precise, which may cause the risk of missing the best opportunity. In a strong market when a stock is exhibiting a strong directional trend, traders can wait for the channel line to be reached before taking their profit, but in a weaker market, they may take their profits before the line is hit (in the event that the direction changes and the line does not get hit on that particular swing). 
Swing trading is one of the most popular forms of active trading, where traders look for intermediate-term opportunities using various forms of technical analysis. If you're interested in swing trading, you should be intimately familiar with technical analysis. Investopedia's Technical Analysis Course provides a comprehensive overview of the subject with over five hours of on-demand video, exercises, and interactive content cover both basic and advanced techniques.
Many orders placed by investors and traders begin to execute as soon as the markets open in the morning, which contributes to price volatility. A seasoned player may be able to recognize patterns and pick appropriately to make profits. But for newbies, it may be better just to read the market without making any moves for the first 15 to 20 minutes. The middle hours are usually less volatile, and then movement begins to pick up again toward the closing bell. Though the rush hours offer opportunities, it’s safer for beginners to avoid them at first.