You can directly click on run job after loading gcode file in repetier, and Accucraft will start printing, but in this case it will wait for the temperatures to reach the set points (this might take 15-20 mins depending upon ambient temperature).
We recommend preheating Accucraft i250 (by turning on heaters before you start slicing and orientation process) so that by the time you orient and slice the parts your bed is hot enough that print can start directly.