While Facebook tends to discourage permanent deletion of any account, it is possible to do with a little bit of help. The only method of removal you can complete yourself is to deactivate the account from Facebook's settings. But before I get into showing you how to fully delete it, it's important to understand the difference between deletion and deactivation.
Deactivating the account means that most of what exists now as your Facebook profile will get temporarily deleted, but you can reactivate at any time to get it all back. Your information, photos and posts stay with Facebook even though it's not visible to any of your friends or anyone else during this time.
Deleting your account means it's gone forever. You're correct to assume this is far more secure and effective at removing your Facebook from the World Wide Web, but it's also the least forgiving. If you ever decide to rejoin Facebook, you'd have to create a brand new one from scratch with new posts, friends, photos and settings.
Before you permanently delete Facebook, there are three things you should consider.
First consider downloading all of your information. You can do this by logging into your Facebook account, then going to your Settings at facebook.com/settings and clicking "Download a copy of your Facebook data" toward the bottom. This ensures the ability to retrieve it all later on after you commence deletion.
Second, know that even permanently deleting your Facebook doesn't get rid of every trace of your presence on the social network. For instance, if you've sent private messages to someone, they don't suddenly delete off of their Facebook. It'll delete you, but not the content of your messages since they get stored on the recipient's Facebook as well.
Third, it can take up to 90 days to permanently delete everything after you put in the request. All of your data immediately becomes inaccessible, but it could still remain on Facebook's servers while the purge progresses.
If you're sure about deleting, just visit Facebook's Delete My Account page to commence.
If you decide total deletion isn't for you, you may instead want to deactivate your Facebook. That's an easier process and far less risky. Just head to your Facebook settings then click Security on the left hand side.
Scroll all the way down until you see Deactivate Your Account. Click Edit, then click Deactivate Your Account.
Once deactivated, all you have to do to reinstate the account is simply log back in at any time.