How do I line up these windows this way?

I was following this really cool build I found on YT, but I cannot for the life of me figure out how she was able to line up these windows along the edge of the blocks like shown in the picture. When I put them down it wants to place them in the center of the blocks as opposed to the edge. In the video she just plops it down effortlessly but I cant get mine to line up the same. Any suggestions?

15. oktober 2026 kl. 06.07