Corners were not a concern. Added 1/4 round.
We tried to space using coins but it wasn’t always perfect. I think it added character! We started at the top and worked our way down completing one wall before moving on. We used liquid nail on the back and tacked down with paneling nails.
Perfect to us!
After hanging all the wood we added 1/4 round to corners and trim to top and bottom. We painted white and done! No more wallpaper!
Wall from first picture.
May not be perfect but much better than the wallpaper lurking behind the wood!