Know the difference between tactics and strategy.
In simple terms tactics are short-term actions that bring a benefit; strategy is broader and about putting yourself in a better overall position, even if there is nothing to be gained immediately.
The best commanders in the military and life are good at both.
Points to note
You can make a good decision and get a bad result, or a bad decision and get a good outcome.
In situations that involve risk, it is important to know whether you got lucky, or whether your strategy is one that brings military success.
Work out how many routes to victory you have (courses of action), and how many your opponent has. It is not numerical/technological superiority that matters, it is how many ways you could convert them into a winning position.
Exploit your image. When there is hidden information, your opponent(s) will be looking for ways to find out more about you. For example, from the tactics/strategy you use, to how long it takes for you assume the (military) initiative, and how you deploy your forces. The image you put across is an important part of a strategy.
The (military) bluff
“Bluffing is not a quirk of human psychology – it is a mathematical necessity.” (Kucharski, 2016, p.33).
Kucharski, A. (2016) Play Your Cards Right. New Scientist. 20 August 2016, pp.31.33.