Facebook is finally joining Instagram in allowing you to have up to four additional profiles under your main account.
Navigate to the main Facebook menu, where a new option will appear.
To switch between your various accounts once you've created them, just click your profile image in the very bottom right corner of your screen and select the image of the profile you wish to switch to. You won't have to go through a login process for each account.
Be aware that your new profiles won't automatically get the notification and privacy settings you already have on your main account. You'll have to go through each profile individually and choose those settings again.
Marketplace, Dating, Payments and Professional Mode also aren't yet available for additional profiles, although Messenger is.