all you do is simply beat match the drums of the original sample...or if you want the time consuming way I'D SAY... get a sample put it in the audio/wave editor when you slice..slice over a drum ....cue it up to go in the sequencer you are using esp if it;s FLSTUDIOS and then wa-la ala replace drums with your own concoction of soft or hard depending on the attack within the original sample of the kicks and time between each kick...damn i'm good