Coming into this season Simmons is 0 for 17 from beyond the arc in his career, but last week he hit a three-pointer in a preseason game against Guangzhou.
"I am confident to say I am not a great shooter," Simmons told reporters.
"I am getting better, though. It is a game. It is five people on the court. I lack something that I am not that great at, but other areas I am very great at.
"I run the floor as well as anybody. Physically, I can rebound the ball at 6-10. As a point guard, I can guard 'one' through 'five'. That is one thing that is coming into my game which I am excited about. I love getting better; I love spending time in the gym and building that confidence."
But while he has struggled with his shooting previously, Simmons has been seen repeatedly making shots in practice and plans to make it a part of his game this season - at least more so than he did over his first two NBA seasons.
"It is something I have been working toward getting better as a player, as you would do as a writer. Everybody works to get better," he added.