Try here first:
http://gbatemp.net/threads/dios-mios-usb-simple-guide.330696/
or
I'll try my best
I'll start from the beginning so you might wanna skip some.
WHAT YOU NEED SD card, USB harddrive(optional), lastest dios mios package, some way to install wads
1. Download the latest dios mios(lite) from
https://code.google.com/p/diosmios/
pick dios mios lite if you are loading from a sd OR pick dios mios if you are loading from a usb haddrive
2. Your SD card must be formatted to FAT32. you can do this by reformatting it and selecting the format to FAT32 on a windows machine
3.If you a loading from a usb then you must also format it to FAT32 too. If it has multiple partitions, the first partition must be FAT32.
4. So now you should have all the stuff you need formatted correctly. For whatever device you will store your games on you need to create a games folder on the root. just label 'games'
5. now go to the dios mios file you downloaded; extract it. We are going to put a game on the SD/USB device. IIRC there is program called DMtoolbox; open that. Select the gamecube iso input box and go find your game iso/gcm. pick an output (i pick my desktop). The check boxs that should be checked are FORMAT: optimized, ALIGN: 32K. Then click install.
6. Once installation is done, go take the new folder and put it in your games folder on your storage device. So it should be SD/USB root -> games -> gamefolder -> game iso
7. all the game stuff is done. now for the hacks. You first need to take the dios mios mios wad that was in the pack and put in your wad folder on your SD card. you need a wad manager to install it. make sure you are using a viable cios during the installation.
8. know you need a loader that can work with dios mios. For now I'm going to do it with CFG. go here:
http://code.google.com/p/cfg-loader/
get that loader and set up the files like it says
9. now go here:
https://code.google.com/p/cfg-loader-mod/downloads/list
and download the file at the top of the list. rename the .dol to boot.dol, than replace the original dol in your cfg app folder.
10. now to try it out. plug your usb to the outer port if you're using usb. start cfg loader.
11. hopefully your game appeared, if it does try it out. if the dios mios splash appears it should be smooth sailing!
ask if you have trouble installing cfg, or what to understand how to use the options that dios mios provides (emulated memory)
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