we have a trust. now we want to change the executor and beneficiaries. how do we do that in california

"Executors" are persons ("fiduciaries" and "personal representatives") who act under a will - not a trust.  The fiduciaries who act under a trust are its "trustees." To change the executor of your will requires a "codicil" (a will amendment) or a new will.  In either event, if you type the codicil or the will you'll need two disinterested witnesses.  They should sign an attestation clause under penalty of perjury.  You and these witnesses should remain in the room while you sign and they witness the will or the codicil.  Typically, if you have a revocable trust the will will be of the "pour over" variety; assets passing through probate administration (wills are "probated" by a court) are distributed to the trustee of the trust.  It is the trust that handles "who gets what." Changing the trustees and the beneficiaries of a trust is a bit simpler.  You draw up a trust amendment (or, if your changes are extensive, a full restatement of the trust).  The person making the trust (the "settlor" or "grantor" or "trustor") and the current trustee will sign the amendment.  If the original trust was notarized, the amendment should be notarized.  You also need to refer to the original trust to see if there are any further procedural requirements.