I don't think it can be under-estimated that the tempo of your project needs to be the same as the sample you're using. "98BPM" isn't good enough most times...it needs to be closer than that. Just forget technique, and bob your head to the music at the same time you're setting the metronome. Try to feel when the tempos are matching. If your tempo is correct (or damn close), you'll have a much easier time chopping things to where they sound in time (because they basically are already). Hope that made sense. Time spent getting the correct tempo is well worth it.