The beauty of Apple's iCloud Backup service is that it runs automatically in the background. Once you've configured it, you're pretty much done unless you want to tweak the settings later. The bad news is that Apple provides a measly 5 GB of free online storage. Want more? The annual fee ranges from $20 for an extra 10 GB to $100 for 50 GB.
Let's say you want more than 5GB -- but don't want to pay for it. One option is to turn off iCloud and use iTunes to back up your photos, videos, contacts and other stuff. Or you could try a third-party cloud service such as Google Drive (15 GB free) or Yahoo Flickr, which offers a staggering 1 TB of free space. A couple of Flickr app caveats: There isn't an iPad-optimized version, and the app backs up photos but not videos.