some people like to pot up in stages; 1 gallon then 2 gallon then 3 gallon and so on, they reckon it allows the roots to increase in a more balanced way. others will only pot twice. some will only do it once, starting and finishing in the same pot. the arguments about the merits of these approaches are endless. personally ive tried all these methods and i cant honestly say ones better than the other. if i am transplanting then i will transplant as soon as i see roots emerging, not just one though its has to be half a dozen or so. have u ever transplanted before? if not then my advice is wait until your plant has used up all its water , then the soil is dry and easier to handle and when u transplant it you should water straight away as then the roots will be ready for water and will stretch towards it.