bold or italic
One or the other, as little as possible
Bold or italic—think of them as mutually exclusive. That is rule #1.
Rule #2: use bold and italic as little as possible. They are tools for emphasis. But if everything is emphasized, then nothing is emphasized. Also, because bold and italic styles are designed to contrast with regular roman text, they’re somewhat harder to read. They’re fine for short bits of text, but not for long stretches.
Nevertheless, some lawyers—let’s call them overemphasizers —just can’t get enough bold and italic. If they feel strongly about a point, they won’t hesitate to run the whole paragraph in bold type. Don’t be one of these people. This habit wears down your readers’ retinas and their patience. It also gives you nowhere to go when you need to emphasize a word. That’s never a problem for overemphasizers, who resort to underlining bold text or using a lot of bold italic. These are both terrible ideas.