Make a copy of your work, then copy that and maybe copy that. That's backing up.
For an effective management of your photos and videos a proper backup plan is as important as the shooting plan. You need to execute that backup plan to the letter to increase the effectiveness of that plan. But what is a typical plan?
Each backup plan is as likely to be different as the individual who uses it. A typical plan could be like this. Carry at least two external hard drives at the location. At the end of the shoot back up your memory cards from your camera to the two external hard drives. Also back up the memory cards to a laptop.
Upon returning back to your office you can then transfer a copy of the images to your primary storage which could be an external standalone back up drive or a network drive or even a cloud storage.
The best solution for small and medium enterprises is at least three backups. One of which should be at an off-site location. That way if your on-site storages get destroyed in some natural or man-made calamity you could still have one external backup that is away from your primary storage location.
For many photographers, amateurs and professionals alike, their primary and only storage is their computer hard drive. That is the ideal recipe for disaster. A million things can go wrong. Your computer get infected by a virus. There could be a power surge completely destroying everything electronic and electrical in your office. Your laptop could get stolen. Would you be ok in the event of any of these predicaments? One advice to you, never make your laptop your primary storage. Or for that matter any storage except your temporary secondary back. That is until you have the three backup storages as mentioned above and baked up your data.