Don't Memorize Your Testimony.
Don't Argue With the Other Party
Address your remarks to the judge, not to your spouse. The only time you will talk to your spouse is when you cross-examine him/her.
Don't wear anything that is sexy!
A woman in court should never wear anything low-cut. Dress as you would for an important business appointment or for church, unless you are being asked to pay support, in which case you will want to dress more casually.
Don't Chew Gum
Don't put your hand over your mouth while you testify.
Don't discuss the case at all in the courthouse hallways, restrooms, or elevators. That nice lady near you may be your spouse's lawyer's secretary.