I've been to NAMM for at least 10 years, on and off. I got passes for at least a decade starting in the 90s. I haven't had passes the past 4 years... I'm still alive. If I really had to get there, I could get hooked up... Most info is online now, including new gear evaluations.
If you have more than 1 day:
Cruise the complete floor noting what's cool to go back to. At least grab a business card for the cool stuff. You don't need every piece of literature available, all this is online now. Look up the gear that night on the net. The second day go back to only what interests you.
If you only have one day you have to cruise the floor fast spending a little extra time at the booths that interest you. The other way if you only have one day is, research what booths you need to see, but even then it's hard to navigate to see them all. You will be walking fast.
In one day I can see the show but I have to cruise the floor fast only checking out what's new and hot. I like to do it in two days. One day to check things out, stopping only at places that "really" interest me, the second day to see the whole floor again bopping from here to there skipping booths at random...
Beware the long demos of one single product that you can get online. Those booths will tie you up.
Go to the shows at night with cool people playing music and stay in a local hotel. I always commuted in so I never had that option. It fun to hands on check out a guitar, keyboard or play with a new piece of cool software. Or complain to a developer why a feature isn't there. I complained to Line 6 they needed someone like Bogner to design the power section to get any decent warmth out of their amp models, only to find out years later they did exactly just that. Manufacturers do listen if you have good ideas. You could also thank the guys who put out the really cool gear you have been using as well
The noise volume can be annoying, bring ear plugs pulling them in/out especially if you have to do a full session the next day. There are "volume cops" that "try" to keep the volume down. Don't bother sellers of the gear too much if you are just checking out the gear. They also have business to do with distributors. That's the point of the show for them.
Somehow every year there is something new and cool...