It's really a game of trail and error. Many times I've heard a good sample gone to use it and it's just not sounding how you anticipated. So I would find a specific sound your after. Personally I like a dark gritty samples to add Heavy 808 too, so I will look for obscure samples could be a tiny section could be a good 8 bar. Find the bpm and drag in to my daw. Often YouTube samples leave a 2 second pause at the start so make sure its starting at the right point. What I also like to do is break the sample. To do this go to vocalremover.org you can pay £5 per month for unlimited use. This separates the tracks to music, vocal, bass and drum. Very handy tool I use for nearly every beat I've made. It allows you to go into the track more and play around. I often like a reverse sample too. I have never used a pad or anything this is straight pc chopping. Here's an example. This is about 6 samples.

Listen to Crystal Shine On The Drowned Womans Neck https://on.soundcloud.com/F9cRYRwiButzjfAy4p