Advice on fitting semi solid floor!!!!!!!!!!!!!?

I am about to fit a semi solid floor(ply on the bottom and walnut on top),i am putting it on top of 2mm underlay.i will leave 10 expansion gap at all 4 walls.i am going to glue each board(tounge and grove).i want to no do i have to put expansion gaps after every few rows of flooring?if so how big of a gap and do i glue it? Please ans asap!!!! Thanks.