I'm glad that you are thinking of adopting. As a member of SCAT I know there are a number of cats and kittens in south Cal.
The only trick we use is a face to face and lots of attention for every one, I have 3 on a transport hold right now, 1 kitten (Rag doll) about 8-9 months, 1 (Persian) about 2 years and a Siamese about 5. The CREW gets along with them and they with the CREW.
Like I said lots of love and attention.