Cool Godzilla creature.
This is not an easy model to start uv mapping with if yr not used to it. If you can I would highly recomend that you pose yr figure into a Zero pose. (you can use Transpose Master for that)
Then go down to yr lowest subdivision and use the ZRemesher in symmetry mode. After that you start to create Polygroups while still in Symmetry mode (X on the keyboard) Mask the area you want to create a Polygroup on. For this one I would have Hands, Arms, Legs and so on. Mask one group at a time and then go to the Polygroup tab and hit the Polygroup By Mask. Do this for the whole figure, and when done you go to UvMaster plugin and select Symmetry and Polygroups. Now you hit the Unwrap button. Once this is done you can start sculpting in details and then texture it.