this is an instructable on how to use Pokesav which can be found here. just click on the download pokesav link and a message will prompt to open it. just download it and open it up, and you should get a window that has a whole bunch of stuff that looks like this.
EDIT: For those of you who want to make legit, super powerful mega charged pokemon, go here. It's a pokedex with all the pokemon and stats and everything you need to know. In other words, check out the pokemon you want to create, make only a couple of the stats maxed out for that pokemon. For example:
Raichu = make Special Attack and Special Defence stats really good because that's closer to normality
Garchomp = make Attack stat really supercharged because it can.
DO NOT SUPERCHARGE LEGENDARIES because now, that's just cheap, rigged,and downright virtually imposible.
Oh, and for that link, there's also a whole bunch of goodies that will help you on your pokemon journey and hacking :). Okay, maybe just journey, but things like damage calculator, balanced team tester, etc will help you lots.
Step 1: Opening a File
unfortunately, this instructable is for those who have supercards or R4s, but im sure you could do the same stuff with an action replay. i think that the main difference is that for the R4 (which i have), you can actually edit the SAV file, and for the AR, its just to input cheats.
plug in your R4 and open the file from the pokesav by clicking OPEN and going to your R4 memory chip.
Step 2: Fiddling Around With Poksav and Your Sav File
now that you have opened your sav file, its time to fiddle and mess around with the stuff you have done. i've played pokemon for a couple months before i realized what pokesav was, so i beat the game and completed the sinnoh pokedex BEFORE using pokesav. i just used it to build my team with sweet pokemon. and i dont go on wifi so it doesnt really matter.
you can do LOTS of stuff with pokesav, like change:
amount of money you have
your rival's name
and many, many more...
Step 3: Changing Your Pokemon
now i will go over how to change your pokemon's stats, and other stuff. just go to the pokemon you want to edit, and click on EDIT. then a window should pop up.
if you have an empty slot in your party, you can make a new pokemon from scratch, but you cant change the sprite. i'll show you how to CHANGE a pokemon's stuff.
Step 4: Changing the Stats
now we can change the stats of your pokemon. you can change any stat you want, and it will make the pokemon better (or worse if you want.)
Step 5: The End
leave a comment if you want me to post more about changing your pokemon and the mystery gifts. have fun with you SUPERCHARGED POKEMON!!!