Simply put, I don't. Not many do other than a good case. Even sealing is relatively rare because the blade gets hard and slippery when you sweat.
My Viscaria is old, worn, beat and full of dents and tons of patches, still plays beautifully, even if it looks more like a bunch of patches with a blade somewhere in there, lost in the chaos of patches on patches.
For my Intensity, I just make sure to take care and not hit it accidentally against the table, and of course put in case when not in use. Sometimes I let it out on my desk overnight if I had a long session and sweat a lot to let the sweat evaporate.
And talking about sweat, sweat comes with a bunch of misconceptions. A good quality blade will not get damaged from sweat alone even a bit. The only effects is that it will get slightly softer and more easily playable, also known as breaking in the blade. Of course colour will change too. If it starts ripping apart because of the sweat, then the blade was bad to begin with.
Blades are meant to be used, if it gets damaged, it's on you. If it wears out because of use then good, you're making use of it. If it gets too damaged to use, buy a new one.
Ryu seung min has been using his racket for decades, his blade is hit a million times and discoloured from sweat beyond recognition. That goes to show that it'll be fine, as long as you don't break it.
Hell, it's enough for an Olympic champion...