Hide it? Here are a few options:
1) Don't hide it all - leave it out openly - hardly anyone will believe that someone could be this brazen about it.
2) Create a folder titled "My Porn" (or something else explicit) and fill it with all your boring stuff; work; etc. - either somewhere inside that folder hide your porn under boring names, or create another folder with a boring name, where you keep the porn. (Most will click on the Porn folder to see what it's about, and finding boring stuff, will then stay out).
3) If your porn collection is less than 32GB - get a SD-Card and put it all on there.
4) If your porn collection is more than 32GB - get an External-HD.