Photos of the accident scene are a must. These will help prove how the accident occurred and which driver was at fault.
Pay attention to detail. For example, skid marks on the road can tell a lot about the crash. You should know that some faint skid marks (called impending skid marks) disappear within a couple days, so it's important to get photos of them right away.
Take photos of the vehicles from every angle to show where the point of impact occurred.
Photos of any visible injuries you have will also be helpful, since these outward signs will fade with time.
If you can, save the clothing you were wearing on the day of the accident. Ruined clothing can tell a story, from rips and tears in the fabric to blood stains from your injuries.
The car itself can be a huge piece of evidence. If it has already been taken to a police impound or wrecking yard, talk to a Rockville personal injury lawyer to see how you can make sure the evidence is preserved.
The more evidence you have, the better the chances will be of winning your case.