1) Create your bochs image and configuration files. I highly recommend installing the OS on a PC before moving it to the PSP (unless you want to spend the next 10 years staring at a progress bar). You can also download some readily available images from here.

2) Download and unzip the files below.

3) If you have 1.0 firmware put the EBOOT.PBP file under the GAME directory (e.g X:PSPGAMEBOCHS where X is the PSP drive). If you have a version 1.5 firmware you need to repackage the file using KXploit. I haven't tested it on a v1.5 firmware so I hope it works. It won't work on newer firmwares (v1.51, v1.52, v2.0) because it's impossible to run homebrew applications on them at this time.

4) Create a directory named VM in the root of the memory stick (e.g X:VM).

5) Copy the disk images and bios files anywhere on the PSP.

6) Edit the bochs configuration file so it will point to your disk images and bios files correctly. Note that on a PSP you have to use the "ms0:/" prefix as the root of your filesystem (see the example configuration in the downloads). Also set the amount of memory your VM will use. Be sure to set it to about 8MB as the PSP will crash if you try to use more (the PSP has about 32MB of RAM total).

7) Rename the bochs configuration file to "bochsrc.bxrc" and put it under the VM directory. This is the only real requirement as the path to the configuration is hardcoded. You can put the rest of the files wherever you want as long as the configuration file points to them correctly. See downloads section for sample script.

8) Run bochs and hope for the best.