I didn't really follow any specific instructions, but here's what I did:
Point the camera towards whatever you want to take pictures of. Try to use the raw mode to capture as much detail as possible.
Take as many pictures of said place as you want. I took about 30, but more images = less noise in your processed image. Since I used my phone for these, I used scrcpy to see and control the device over usb adb, mainly because I didn't want to accidentally move the device it while trying to take the next picture.
Post processing the image was done in gimp. The tif files deep sky stacker exports are usually wayyy too dark, so you'll need to adjust the brightness.
Pro tip: try to keep trees and other landscape out of the frame of the photos because deep sky stacker tracks the earth's rotation, meaning the landscape will be blurry.
Take a look at stellarium. It's an app that uses your phone's compass to show a map of the stars. I've not used it as my phone has a god awful compass so the map is inaccurate.