Don't SAY anything.

That's the most difficult part for me, because I can be a little shock-y and not entirely rational. I'll be processing what I did wrong. The cop may even ask you what you did wrong (he did the last time I crashed my m/c). There's almost always something, but that's very different from legal fault. If you admit what you should've done to avoid the accident, the cager will latch onto that as an excuse for hitting you.