Keeping track of the markets is amongst the more stressful jobs around. And believe me, job stress is pretty common. Amongst the most cited trigger of job stress is the lack of workplace predictability. Since trading is all about unpredictability, the stress is natural.
The pressure of making quick and multiple decisions in a day can take its toll on our brains, and when the chances of those decisions being wrong are high, then the stress starts to multiply.
One of the best ways to deal with stress while trading is to acknowledge that unpredictability is as much a part of the job as the stock market is!
Once you have that fit into your thought process, start to filter out which elements of trading are in your control and which are not. Market fluctuations are beyond anyone’s control, but your trades, and whether you book gains or losses are in your control to some extent. Once you accept the cause of the stress as part of the trading cycle, you will be able to cope
Coping will require that you make boundaries to specify what is possible for you to do and what you can't do. For example, if the market drops 50 points, you can't control that, but how will such a drop affect your trades? Work it out on your spreadsheet. Use this knowledge to improve your strategy.
Make scenarios of things that cause you to stress and see how it affects your trading goals. By focusing on the bottom line and what you can control (and what you can't) you can redirect your nervous energies towards making the most out of your stressors.
Acknowledging that stress will always be a part of your trading routine will help you address it healthily and positively.