Question re url before I start

[banter]

I am new to GetSimple. I only do web design as a hobby so please bear with me. I've easily installed GS onto a sub domain of another website I have. However I want to eventually move the website to its own full domain (once I decide on the exact url). Is there going to be a problem with moving it if I start work on it now, or would I be better to just wait and install it properly on the right full domain to avoid problems?
Many thanks!