If you have just witnessed an injury like a fall from a bike ride, use the video feature on your phone to capture the whole scene as soon as possible before moving the patient. If that's possible.
A few photos are great, but you are not a trained specialist, and it does not tell the whole story of the injury.
Take a video of the whole scene. If you or someone happened to capture the actual fall, that's even better and a lot of people do like to capture a trick maneuver etc. They want to piece together the sequence of events leading to the injury rather than the injury itself. This will aid in people to check other areas of impacts that could be missed.
If you are videoing the injured area, also try to cover from all different angles. For example, if there is just a photo of a broken skin, they would not know left or right side of the body.
The video will capture the time of occurrence, which is important for them to know the amount of time passed before the patient was brought into the care facility.
Providers using products like WinguMD can import your videos to their EHRs for future reference.