*All links have been updated and are working as of Jan 2018*
Setting up homebrew is considerably easy and is reccomended if you would like a wide range of customization and control on your Nintendo Wii.
Requirements:
Nintendo Wii
SD card
Computer
Step 1:
Download the Homebrew channel by going here http://please.hackmii.com/ type in your MAC Address which you can find in the Nintendo Wii settings under internet, then type it in on letterbomb and cut the red wire.
Step 2:
After the Letter Bomb files download, insert your SD card into the Computer. Make a folder called “apps” on the root of the SD card. Drag the Letter Bomb files ;”boot.elf” and “private” onto the root of the SD card (Not into the apps folder).
Step 3:
Eject the SD card and insert it into your Wii. Turn on your Wii, go to the message board and select yesterday. You will see LETTER BOMB there, click on it. Follow the on screen instructions.
If you want to download the Homebrew browser click here
Need advice on how to set it up? Click here
If you have any problems please comment and I’ll do my best to help.
Wii Homebrew 
If anyone is confused, you have to go into your Wii settings and find your MAC address.
LETTER BOMB doesnt work on My Wii mac Add I GET THIS ERR
The exploit will only work if you enter your Wii’s MAC address.
Okay. I have a new wii and no matter what I do, the letterbomb won’t show up on any day of the message board. I’m using an sd card that I’ve used to softmod a previous wii. Both wii and sd card have been reformatted multiple times. I’ve checked the MAC address and the compiler. The only 2 files on the sd card are the private folder and boot.elf. I’ve changed boot.elf to boot.dol with no success. I’m definitely on a 4.3U wii. I can’t afford to get anything new sd card or wii but I can’t find any reason why either of them won’t work with letterbomb. I’m officially stumped.
same issue here for me too. Although my version is 4.3E not U.
Hey guys consider checking out the subreddit r/wiihack the users their are very helpful in sorting out issues related to soft modding your wii!