There are a lot of ways to approach what can be a very daunting part of the writing process. In my opinion, you should write your fight scenes like a dancer would write their performance. Talk about it like an overall experience first, then obsess over the parts that were important to your character.
Blow for blow is a little dull and gruesome, and while people don’t necessarily understand the mechanics of a particular fight as well as sex, they understand that they are probably going to be trying to hit one another.
Again, the actual fight itself is rarely the important thing. It’s the conflict coming to a head, one person winning out over the other or escaping in the end. Maybe it’s the climactic conclusion where they both die. Overall, the important thing about most fight scenes is not the fight but the conflict that the fight represents. The styles of fighting typically describe the characters.
When you focus on the blows or attempted blows of the fight, focus on the pivotal moments of it and the parts that define the characters. Backstabbing, any hesitation moments or moments where there is no hesitation at all when there might have been, moments when they go in for the kill and where they are looking when they do so, when one person gets the upper hand over another and how, these are important moments that should get a bit of a focus because they can further illustrate the characters involved.
The rest is about everything but the fight. The feeling of the ground under their feet. The weapons in their hands. The pounding in their chests. The sun in their eyes. The blood trickling out of open wounds. The pain as they try to balance on broken limbs. Make it a visceral experience.
There are exceptions to this, of course. If you want to do this more from the perspective of a cold killer, on the other hand, describe every single blow. That makes it more cold, mechanical and removes any of the emotion from the battle. Removing the sensations can make it feel dull and monotonous, like an office job.
