Transparent/invisible preset parts?

[Willowleap]

I was wanting to to little invisible parts in my preset to  make the fur look a little more fluffy - but im unsure how to do this? I would rather have a picture tutorial if you can D:
Please help?

[OreoHeroz]

Take a look at Ruby's transparent guide: <here>

You can see her whole guide list (different material codings) <here> if you prefer.

[Willowleap]

Thank you x3