Step 11: Select All The Strip Intersection Points

We have our vertical and horizontal strips, but all it really looks like at the moment is that we have a bunch of black squares covering our image. We need to create the illusion that the strips are weaving above and below each other. To do that, we need to select the areas where the vertical and horizontal strips intersect. Before we do that though, press Ctrl+' (Win) / Command+' (Mac) to turn off the grid if you haven't already, since we no longer need it. Then, hold down your Ctrl (Win) / Command (Mac) key and click directly on the "Horizontal Strips" layer's layer mask thumbnail:

This will load the horizontal selections back into the image:

Then hold down Shift+Ctrl+Alt (Win) / Shift+Command+Option (Mac) and click directly on the "Vertical Strips" layer mask thumbnail:

This will do two things: One, it will load the vertical selections back in to the image, and two, it will tell Photoshop to keep the selection around only the areas where the horizontal and vertical selections intersect. Everything else becomes deselected:

Step 12: Save The Selection

Before we go any further, we need to save this selection. To do that, go up to the Select menu at the top of the screen and choose Save Selection. When the "Save Selection" dialog box appears, simply click OK in the top right corner to exit out of it:

Step 13: Deselect Every Other Square Selection

With your Rectangular Marquee Tool still active, hold down your Alt (Win) / Option (Mac) key and drag a selection around every other square selection. This will deselect the selections you drag around. Continue dragging around every other square selection to deselect it until only half of the original square selections remain. Your image should look like this:

Step 14: Copy The Selection To A New Layer

Click on the "Horizontal Strips" layer thumbnail in the Layers palette to select it. Then press Ctrl+J (Win) / Command+J (Mac) to copy the selected areas to a new layer. You won't see anything happen to the image itself, but if you look in the Layers palette, you'll see a new layer named "Layer 1" added between the "Horizontal Strips" and "Vertical Strips" layers which contains our square selected areas: