As Paul mentioned, there are many ways to approach this.

Personally, I import the recording into my sequencer and try to match the beats of the recording to the bar/beat map in my sequencer. This can be time consuming but it is worth it in the end. You need to make adjustments for tempo changes or meter changes etc.

Then I simply play along with the recording playing each part one at a time. Starting with the drums, Bass, melody and then I try to add everything else I can hear.

Once I have recorded one track I mute it so that the next instrument I record is the ony thing I can hear.

When I have played all the parts I mute the original and playback all of the tracks that I have recorded.

Usually I get a reasonably faithful representation of the original because I have played it using similar velocities etc because I have played it along with the original.

Then its just a matter of mixing and adding any detials I have missed.

Again, this is just a personal preference but it may be worth giving it a go.

Simon