How do you mix mods together?

[wampa2]

For example, I would like to use 90s re-imagined mod's Claire's head and hair with the motorcycle policewoman mod body. Thank you. I tried replacing specific folders (such as folder l1050 for head) and make a rar file out of the entire mod and drag that into fluffy, but fluffy doesn't recognize it and it doesn't show up on the mod list. Thank you.