I’ve — very quickly — dashed off two demonstration videos that show an approach to layering. In these films, I’m basically talking and using Reaper at the same time, not always in perfect coordination, but it shows an approach to stacking sounds together to make enriched composite gestures.
The first video shows me layering some gas sounds together to make gesture based on an original shape. I also improvisation-ally mess around with some reverberation. I’m not saying that you should use reverberation in your library sounds, in general that’s definitely something to avoid baking in, rather, in the video I’m trying go against its spatial signature, trying to turn into a composite part of the sound itself.
The second video shows another approach attending to spectra in a more deliberate way, listening for parts of original library sounds that might layer up neatly together because they occupy different parts of the spectrum. There were some nice flukes that I just went along with.
What I don’t show is masses of detailed fussing over EQ and dynamics… it’s up to you how far you choose to go with these things.