Attachment is fixed. Document sample shows places for two witnesses. If witnesses don't already have their own seal then they may print their name along the inner border, thumb print in red or blue or draw/print out their own seal symbol.

"In California I have filled out a Statement of Facts with, "I want to junk this motor vehicle".

The DMV provides the form.

I received a receipt on the spot. If there are outstanding parking tickets attached to the account they may pester that those need to be paid first. One time I was in front of a friendly clerk who said that I could pay them later and then the "junking" process would be completed but she handed me a junked status receipt anyway. I walked out to the vehicle that now had a junked CoT and drove away.

For those who are not convinced of the status after these steps they may always ask an officer to run the VIN.

I would save the junked receipt in case the vehicle is sold to another party who wishes to put it back under a "STATE OF... " security interest. (Wants to re-register it.) They will need the receipt.