Well, first you have to be tall. Unless your name is the current Isaiah Thomas of the Celtics, or Stockton, or Iverson, or maybe in a former life you were called Spud (Webb).
You definitely have to have a good outside shot. Unless your name is Shaq, Wilt, Worm, or maybe that Andre guy that plays for the Detroit Pistons.
No doubt you must be in good shape and fleet of foot. Unless your name is Barkley, Laimbeer, or you just got off the boat and play for the Nets.
One must be quite adept at passing to teammates. Sharing the ball, as it were. Unless your name is Kobe, Carmelo, or used to be called Chocolate Thunder and you broke a few backboards in your unbridled enthusiasm.
Playing tenacious defense is an absolute necessity. Unless your name is the above-mentioned Carmelo, or you once had the late and former UNLV coach Jerry Tarkanian as a mentor. Or -- you used to answer to the name Iceman, Dr. J, or Pistol Pete. Score 30 a game and maybe you can slide on the D.
You have to have some brains about you. Of course the bar is fairly low here. Put another way, if you can sign multi-million dollar checks and get a few tats, you probably pass the IQ test. A word of caution. Don't bother getting in touch with the MENSA folks. Chances are good you won't gain admittance to their club. But hey, even those guys/gals appreciate a good joke once in a while, so maybe try it once just for grins -- even if it's theirs.
For damn sure, any player that has made his way all the way up to the NBA -- MUST be able to shoot free-throws reliably. Unless your name is Shaq, Deandre, or that Andre guy from the Pistons again. Ignore them, because they are obviously laughable exceptions to the rule. Those guys couldn't throw a brick overboard in the Pacific ocean if their boat was GPS equipped halfway between California and Hawaii.
If you came from a big round ball factory school like Kentucky, Duke, Carolina, or maybe Michigan State, your chances are better to get a serious look by the pro teams. If you came from some little twerp school like Davidson, you're in big trouble. Unless your name happens to be Steph and you can shoot the lights out. And hey, take heart, ye that never even set foot on a college campus, let alone ever passing a class of higher education. Those Lebron and Kobe dudes seemed to wind up doing OK. Alas, these days they make you wait a year after high school until you're "mature" enough. Somehow the powers that be consider you a know-nothing boy at 18, but acknowledge you as a man ready to conquer the world at 19. Right.
Besides the above-mentioned qualities, though their are exceptions, it's really, REALLY helpful if one just happens to be 7 feet tall, can talk trash, and don't forget about the tats. Load up on those.
If you're an inked up behemoth with an attitude, it doesn't matter if you possess the intellect of your average green bean. Worry about that later, because cleaning that up to the ever-gullible public is what agents are for. Better yet, the always politically correct talking heads on sports channels will find a way, SOME way, to portray you as a superstar that can seemingly do no wrong. Everybody's a hero in their eyes. Might as well enjoy it, even if you're the last guy on the bench on a last place team. You da Man, according to them.
You might want to limit impregnating different women to a rather low number, say 4 or 5, lest those pesky child support payments come back to haunt you after you've bombed out of the league and are basically broke already, Yeah, the so-called fairer sex can cop an attitude like that sometimes. Go figure.
Try not to crash too many luxury automobiles and staying away from serious drugs is usually a good idea. But it's OK to do a line once in a while or smoke a bunch of weed in the off-season, as long as your agent is well enough connected to inform you well in advance when those dreaded drug testing nerds will be heading your way. Piece of cake.
All in all, it's a pretty decent gig, and you can have it if you act right -- at least to start off with. If you don't know anything when questioned, and those moments will come, just say "ya know", "uh", or "um" a lot, and smile. Smiling is good. Temperamental brooding is not, Unless your name happens to be Boogie, and he just got a ticket out of town from the lowliest of the low Sacramento Kings.
Confidence is good. Arrogance and cockiness -- not so much. Witness that Westbrook guy from the Oklahoma City Thunder that continues to spout off to other players while padding his own personal stats. See the Thunder get clobbered by good teams that are unselfish and function as a unit. Lots of money for Russell? Yes. Will he ever taste a championship? Not a chance.
So the bottom line is -- learn how to do something really, really good if you're not 7 feet tall. Maybe they'll find a spot for you. Even if not, there's worse things than working the midnight shift at IHOP.