Rees was slapped with a 12-week ban in January after being found guilty of making contact with the eye area of England hooker Dylan Hartley.
The incident occured as Cardiff's second European clash with Northampton Saints boiled-over in December.
But Rees has now served almost 10-weeks of his suspension and is beginning to ramp up his training as he looks to make up for lost time.
"The ban was hard to take especially with what went on behind the scenes," said Rees.
"But it's done and dusted and I'm looking forward to getting back to rugby.
"I'm back for the Blues' last five games and hopefully the World Cup warm-ups with Wales. I can't wait to pull my boots back on.
"This is the longest I've ever been out but it's given me a chance to have a rest and get my hunger for rugby back.
"I've been doing a lot of work with Gethin Jenkins, who had his operation the week after I got banned. We've been training partners in the gym and he's been dominating me.
"I've also done my first few rugby sessions in the last week and I'm looking forward to getting back on the field."
Rees is free to play from March 31 and could be set for a comeback in the Magners League Welsh derby against the Ospreys on April 2.
"I want to hit the ground running, the Ospreys would be my first game back and hopefully I'll be involved," added Rees.
"It's a massive game against a team I've played for. It would be great if Mike Phillips' is playing as there's always great competition between us.
"Rugby's something I love doing and hopefully I can help push the Blues on to stay in the play-off spots."
Rees admits he fears for his place in the Welsh set-up after being ruled out of the entire RBS 6 Nations.
But he is hoping a quick return to top-form with the Blues will pave the way to a place in Warren Gatland's World Cup squad.
"It's been frustrating because the Six Nations is a tournament you want to play in.
"I was lucky to play in almost every game for Wales last season and wanted to do so again.
"Every time you're not playing you're missing out and there's a lot of competition at scrum-half.
"Everyone wants to play in the World Cup and I am looking to get back into the Welsh squad."
But Rees will first have to overcome the challenges of a crop of young scrum-halves at the Blues. Gareth Cooper's retirement earlier in the season left Rees and 21-year-old Lloyd Williams as the Blues' front-line scrum-halves.
But when Rees was hit with his ban and Williams suffered a shoulder injury, young duo Rhys Downes and Tom Slater were thrust into Magners League action.
The pair have done a fine job in the number nine jersey as Cardiff continue to push for league glory. And Rees has been impressed by the way they have filled his boots.
"Tom Slater and Rhys Downes have done very well and taken their chances. Lloyd's also back the week before me so we have people coming back and a bit of competition.
"Hopefully we can continue the push for the Magners League title."
Guinness PRO12
Suite 208, Alexandra House,
The Sweepstakes
Ballsbridge, Dublin 4, Ireland