Ever wondered how you can create isometric maps for your dungeons? Well, the easiest answer is an isometric grid. You can actually purchase this at shops, but I am happy to share a half-inch a quarter-inch version of this with you if interested. One is portrait and other one is landscape.
Thing is you might need to print this, or use in in a tool like Photo Shop as background layer. Note: I used in Sketchbook Pro. Speaking of which… you actually wanted this a Photo Shop .psd? This is your lucky day – here are the ZIP files for that at this GOOGLE DRIVE LINK.
What this looks like, when I am working on it:

What can you actually create using this? A couple of examples below…