Wait until it has got its first two true leaves, the serrated ones, and you can see the next two already forming. Although transplanting now is possible, waiting until the plant is a little bigger will avoid any risks associated with handling the baby/new seedlings. Once they have the first true leaves they are more able to make use of the light. At this stage that it is at now, the plant is trying to establish a root system and get the first true leaves to function. Any interference at this time may "upset" the newly hatched seedling, all for the sake of not waiting the extra day or two before she is a fully functioning and self supporting being. Hope this helps,..... Organoman.