The interpreter interprets for the speaker. SPEAK SLOWLY so that the interpreter can interpret for you. English is best understood slowly, rather than loudly.
SPEAK DIRECTLY TO THE CLIENT. "I want to ask you some questions."
Make eye contact with the client. Spoken language is only a small portion of communication. Much can be learned from body language and context.
SPEAK SIMPLY and avoid legal jargon. Avoid using legal vocabulary and instead explain the meaning of a legal term. "On Monday, we have to go to Court and talk to the judge. The judge will decide how much child support you will get after the judge reads your financial statement."
Use the interpreter as you would a telephone. The interpreter interprets for you when you are speaking. Do not ask the interpreter to meet alone with the client to prepare any documents or to discuss the case. The interpreter is your intermediary to communicate with your client.