If you are going up 1 hole step the chord you would use is a seventh chord based on the sixth step of the key you are in. This ends up being the V seven chord of the new key. Example when in the key of G the I chord is G the IV chord is C and the V chord is D7. To modulate up one step play the VI 7th chord, in this case E7. Up one step takes you to the key of A. The chords are I-A, IV-D, and finaly V7 is E7.