When I first started thinking about making characters for mugen, I was a little bit confused about how to get my ideas down, and I didn't really think about searching the website at the time I started with my ideas, but I've come up with a layout for ideas for new characters. The funny thing is that my idea goes right along with [C]yanide's self taught codework. Here it is:

Character Name:
Here you just state the characters name, and give a details to keep yourself reminded of what the character's personality and looks should be like.

Outfit(s):
Here is where you'd plot out you ideas for outfits, whether it be one that's a bunch of different colors or just a bunch of different outfits.

Attack Style:
This would be how you'd want the A.I. for the character to be, whether it be aggressive, elusive, smart, whatever you feel the character should be like when fighting.

Moves: This is how my basic layout starts.
Moving:
Forward- Walk
Back- Walk
Up- Jump
Down- Crouch
Tap Forward then hold- Run
Tap Back twice- Dodge Back
Block-
Standing:
LP-
MP-
HP-
LK-
MK-
HK-
Crouching:
LP-
MP-
HP-
LK-
MK-
HK-
Jumping(Up):
LP-
MP-
HP-
LK-
MK-
HK-
Jumping(Forward/Back):
LP-
MP-
HP-
LK-
MK-
HK-
Grabs:
Once I get to this point, I start naming moves and showing the input commands for them.
Specials:
Supers:

Win Poses:
This is self explanatory.

Intro(s):
This is too.

Opponent Rivalries:
Now this would be the characters that you want your character to interact with and how you want them to interact.

This is a pretty simple system to use to make characters. I'll put an example below, with fake info that I don't intend to use, so if someone else decides to make a character off the example, they can have it, I'd just like to be accredited for the thought.

Sho-Joe:
Japanese soldier who practices mixed martial arts and has elemental attack power of lightning. Stance similar to Guile(SFA3), but hair is short and dark.

Outfit(s):
Camouflage white and red pants, black tank top.

Attack Style:
Defensive. Would be better to sit back and wait than to rush in and attack.

Moves:
Moving:
Forward- Walk
Back- Walk
Up- Jump
Down- Crouch
Tap Forward then hold- Run
Tap Back twice- Dodge Back
Block-
Standing:
LP- Jab
MP(standard)- Hook
MP(forward)- Gut Punch
HP(standard)- Straight
HP(close)- Hard Uppercut
LK- Shin Kick
MK- Side Kick
HK(standard)- Roundhouse
HK(back)- Flip Kick
Crouching:
LP-
MP-
HP-
LK-
MK-
HK-
Jumping(Up):
LP-
MP-
HP-
LK-
MK-
HK-
Jumping(Forward/Back):
LP-
MP-
HP-
LK-
MK-
HK-
Grabs:
Suplex(b+HP)- grab opponent and slam them on back
Specials:
Shock Bolt(d,df,f+any P)- throw elertrical boomerrang that stuns opponent, lowest level 1 hit, highest level 3 hits
Flash Slash(d,hold 2 sec,u+any K)- attack similar to Guile's Somersault Kick, but attack shocks opponent
Supers:
Super Flash Slash(db,hold 2 sec,df,db,uf+any K)- attack with multiple somersaults that electrocute enemy, 9 hits
Win Poses:

Intro(s):

Opponent Rivalries:
Guile - each character salutes the other

It's a simple set up to help keep your ideas organized. I didn't see any posts like this one up and I'm sorry if I repeated something that someone else has already said or done, but I thought that it would be a help to other noobies like me that have been having trouble keeping all of their thoughts organized for when they actually program. I'll admit though that this is a little bit different than the way I actually used the layout, but that's because I'm adding something to my characters that I want to release as an original idea, at least I hope it's original. Anyway, I hope that I was helpful, and if my guideline looks confusing in anyway and you have questions to ask me, don't hesitate please.