When you lead you can only do so having clarity. That means first and foremost clarity in your head. The way your head looks like in the inside determines the way your solution will look like in the outside. You must understand the problem or issue you are up against.
Here's a test: describe the problem on one page. Then, distill the essence of the problem. Reduce it to one sentence with 10 words or less. For beginners: do that in one hour or less. Time constraints will keep you focused. After all, in many situations you will encounter, you won't have that much time. Let alone in crisis.
Show it to your team members. Do they, can they understand it? Does it make sense to them? If not, you are still confused. A confused person cannot lead. You might have to repeat the exercise as often as needed to get the essence crystal clear. Over time you will get pretty proficient with it, developing your ability to almost instantly recognize the core of the issue.
I don't care whether you are dealing with complex or complicated environments. If you can't do that, you cannot lead.
Always be clear. Do your critical thinking.