The 22-year-old experienced an important season last time out, as he built a strong partnership with Perry James and finished with averages of 8.5 points, 2.4 rebounds and 1.5 assists per game in 19.7 minutes per contest.
"I'm definitely putting in extra time, trying to stay focused and just finding other ways to score as well and little things to add to my game," Lamb told NBA journalist Nick Gallo.
"I'm just having the mindset to continue getting better.
"I'm trying to pick up full court and stay in front of my man. I think I've been doing that better. I'm getting around screens. Offensively I'm just attacking. I've been getting to the rim a lot better. I still have to work on the finishing part."
The new NBA season is due to commence on October 28, with the San Antonio Spurs opening the first game against the Dallas Mavericks.