Naismith suffered the second ruptured cruciate ligament of his career - both knees have now been affected - during a win over Aberdeen in October.
The Scotland international will be out for the rest of the season but he is confident he will make a full recovery.
Naismith told Rangers TV: "It's coming along nicely and I feel pretty good. The leg seems strong and the physios and the doctor are happy with it so it's a case of continuing on.
"We are still at an early stage and I am only doing basic exercises at the moment. It will be another month or so before I can do harder exercises.
"There are different phases to the rehabilitation. At the start the surgeon just wants the graft to heal and the scars to heal over, then it is to get your range of movement back followed by the hard work to build your muscles back up.
"The early signs are that everything will be fine. We have worked hard to get over the first few hurdles.
"Having been through all of this before it has helped me mentally. I am much more comfortable going through all of the exercises asked of me whereas in the past I was more apprehensive."
While Naismith faces his own personal battle, his team-mates now face a fight to claim their fourth successive Clydesdale Bank Premier League title after being overtaken by Celtic.
Rangers had been 15 points ahead in early November but their 1-0 defeat at Parkhead saw Celtic move two points above them.
However, Romanian defender Dorin Goian, who returns from suspension for tomorrow's visit of Motherwell, is determined to turn the tide.
The centre-back said: "People should remember that the championship is long and there are still many games to play.
"I still think it is in our hands to win the championship.
"We have to rediscover our confidence and I think we can do that against Motherwell and win the game. If we do that it will give us a chance to put things back to normal.
"When you have tough moments you have to train harder, you have to find something extra to recover and I feel we can do that.
"I feel the team we have is capable of winning the title. We have made a couple of mistakes and we have paid for them but I am very confident we can still win the league."