At the end of the day the only thing that matters to the client is the footage that you collect, so making sure it is all recorded properly and stored safely is key.
Make sure to swap out your media cards and backup to another device throughout the shoot. You don’t want to be using a single card all day and end up losing your UAV or corrupting the media on the last shot of the day.
Try and swap media cards every second or third flight as a safe minimum, more so if you are over or near water.
You also want to ensure the footage is usable as well, and that you don’t have corrupted files, a focus issue, vibrations, etc. Better to check throughout the shoot than find it’s no good after a full day.
Reviewing the media will also provide a break from the pressures of flying and allow you to regroup and take a breather between takes. It will also show if you need to redo any shots that may not be up to par.
Label your cards with a unique numbering/index system so you can easily distinguish between them and note the cards that are used/unused; you don’t want to accidentally format and overwrite a card filled with great media by mistake. Keep the cards in a safe secure place so they don’t get lost.
When your back at your home base make a local and offsite backup of the media as well, you can never have too many backups and storage is cheap in comparison to the time and effort put into getting the imagery. Services like Dropbox make for an inexpensive and easy means to keep a central offsite backup that is accessible to all your team as well as to the client.