Looking up is always the right direction. Here are a few examples of how you can get going the right way when it comes to “up” words. You’ll find that hyphens are often used.
- mix up: two words as a verb. For example, “I’m going to mix up a batch of cookies.”
- mix-up: hyphenated as an adjective or noun. For example, “Please pardon the mix-up.”
- setup: one word as a noun or adjective. As in, “What kind of crazy setup did they have at the event?”
- set up: two words as a verb. For example, “I need you to set up that meeting, please.”
- start up: two words as a verb. “Start up the car; I’ll be out in a minute.”
- start-up: hyphenated as an adjective or noun. “The small start-up was known for being nimble and innovative.”