quick guide...
copy and paste the text you want into a .txt file
run that .txt through the supercard cheat generator, cht2supercardcheat.exe available on the SC site or just google it.
hit the 'make book' button, and it will generate a .scb file (supercardbook file)
name .scb same as the .nds file and put in same directory, or name it romnumber.scb (such as 0001.scb) and place it in the scshell\book folder
note that the ndsinfo.dat file needs to have the rom listed for it to find the correct .scb file in the book folder, but naming and placing it with the rom will always work.
finally hightlight game on the scds1, press x, then choose 'patch options' and tick 'enable book' and save
now when playing that rom you can call the guide up by pressing.. L+R+Start+Down