This is one of those forgotten about elements but is super important and in my opinion the first question you should ask every wedding photographer! In a nutshell, I always keep at least 3 copies of your photos (2 hard copies and a cloud backup). On the day I have two camera bodies and a spare in my bag and all of my cameras save to 2 memory cards. The first thing I do when I get home is back up your photos and I keep everything on a hard drive until your gallery is delivered.