To change the blade on the table saw, do I pull the wrench toward the front of the saw to loosen the nut?
If the arbor enters the blade from the left side of the saw (as most do), you need to rotate the top of the nut toward you to loosen it, away from you to tighten it. Note that this way, forces on the blade tend to keep the nut tight rather than encouraging it to work free.
The manual is the bible of your tablesaw, of course, but being a bit dyslexic, I need all the help I can get in situations like this, so I've developed a couple of habits I find useful.
The nut on my tablesaw arbor is the only left-handed thread I have to deal with regularly. Since it is on the left side of the blade, I consciously only loosen it with my left hand (I'm right-handed, so most off my threading tasks are done with my dominant hand). Muscle memory helps me remember which way to turn it.
Also, my saw requires brace to hold the blade against the force of the wrench. I know I'm loosening when the blade's teeth bite into the brace.
On all table saws I've seen rotate the wrench on the nut in the same direction that the blade spins to loosen the nut (regardless of which way the arbor is mounted).
I can't imagine that it would be threaded the other way, because of safety, but who knows.
But like Matt mentions in a comment the manual will have the correct instructions.
Sometimes you have to give the wrench a few light taps if the nut has tightened up from the blade spinning.