I have just bought some wooden flooring and having only occasionally laying it before i have a problem with this bigger room

the 4 planks i am using when laid down are the exact same length as the room in the past i have had to cut the last piece in half and then use that to start the next row but how do i start the next row if the first row fits exactly from wall to wall?

Just cut a piece in half and use the 2 halves at either end.

Hi
Try the same way you started the first row, I presume you cut off the tongue or groove to start, what's with this cuttinging in half you just cut to fit

The above comment is odd as as you use the blank/cut end from the previous plank/board abating the wall and the grooved/ tongue end for the next plank so there is no waste

You're supposed to stagger the way that the boards are laid in the same way that bricks are staggered for rigidity and strength. If you lay them aligned by length and width the point where the four corners meet will be a weak point. Given the boards won't be perfectly straight and will warp and move slightly with moisture and heat you want to minimise this on the visible surface. Without the staggering it would allow movement across the floor as well as along it and eventually it may weaken and bow up. I've seen this happen.