Hmm, stuff that is not in the AFM...
Presume you will be getting a job as FO first. Spinning the props after shutdown -- a few M23 pilots spin the props so hard that it indicates on the torque guages. This is not necessary. All you are trying to do is dissipate residual heat, pulling through the required blades at a reasonable speed will do this.
Setting takeoff power. On hotter days you will be EGT limited rather than torque limited. The engines have overtemp protection with the fuel bypass, but if you rely on that you will miss out on a bit of power.
Set the power initially so that EGT is just under 740degrees. Observe it rise during the TO roll and adjust. The fuel bypass should protect against overtemp, but it is fairly coarse adjustment and you wont make as much power as you could if you carefully set TO power.
"Wet" takeoffs. You should experience one in your endorsement. Be ready to adjust power after turning off the CAWI pumps at acceleration altitude. It feels like the bottom falling out of the aircraft the first time you do it. Be cautious that you dont select Reserve power as you turn CAWI off.
As I write this, I seem to remember that there was a thread on this stuff last year. Why not try a search?