As I mentioned before, I don't have the patience to lay out a large wall with blanks, so here is my tutorial on how to lay out a wall.
This room has a slanted ceiling, going from 9' at the left to cathedral height on the right. I knew I wanted to cover the entire wall in photos, so I started with the highest side. With a gallery wall, something that will drive you crazy is if the frames are not straight, so I chose to put three nails in the wall for each frame to keep it level.
To start, you need to put one nail in the wall in the center of where you want the first frame to hang.
Next, I used my iPhone and an App called GyroLevel. I held the frame and adjusted it until it was level. Then, using a pencil, I drew a line along the top of the frame.
The next step is to measure from the line to where the nail is on the wall. To make it level, all three nails need to be the same distance from that line.
I then moved the ruler equal distances on either side of the first nail, and drew a dot where the other nails would go.
Then simply hammer in the nails.
Finally, I used the level again to adjust the frame to make sure it was perfectly level.
For the first three frames along the top of the wall, I made sure that the frames were equal distance apart horizontally. I also made each step down the same distance from the top of the wall. Then I began to add other frames in, maintaining the same distance between the frames.
As you can see, I then filled the rest of the wall in with other images, working around the furniture.
I did the same thing on the adjoining wall. The space to the left of the TV, and the right of the desk/chandelier, is where the new chair will go - when I find it!
Pardon the mess in the room on these photos! It is still a work in progress! I hope my technique is helpful!