A modulation chord that will allow to modulate from anywhere to anywhere is by playing the 4 chord with the 5th of the key in the bass of the key you are going to. Just in case that makes no sense, here is the illustrated version:
"Modulating" by: T-Block
LH/RH
Modulate 1/2 step up
C / G-C-E *old key
Ab / Gb-Bb-Db *modulation chord going to the key of Db, 5th of Db in the LH, 4 chord in the RH
Db / F-Ab-Db *new key
Modulate 1/2 step down
C / G-C-E *old key
F# / G#-B-E *modulation chord going to the key of B, 5th of B in the LH, 4 chord in the RH
B / F#-B-D# *new key
Modulate more than 1/2 step up
C / G-C-E *old key
B / A-C#-E *modulation chord going to the key of E, 5th of E in the LH, 4 chord in the RH
E / G#-B-E *new key
Modulate more than 1/2 step down
C / G-C-E *old key
Eb / Ab-Db-F *modulation chord going to the key of Ab, 5th of Ab in the LH, 4 chord in the RH
Ab / Ab-C-Eb *new key
You see how that works? If you have no knowledge of music theory, then you need to visit the music theory forum and start learning.