Unfortunately, I'm afraid it's mostly stuff one needs to know by heart, but I think it's often that the noun is the one that is all in one word and the verb is the phrasal one (composed of "base" and the particle, in several words). Note: I'm not a native English speaker.
- set up [1] (notice that it's a verb)
- setup [2] (notice that it's a noun)
- Phrasal verbs [3]
Unfortunately, I'm afraid it's mostly stuff one needs to know by heart, but I think it's often that the noun is the one that is all in one word and the verb is the phrasal one (composed of "base" and the particle, in several words). Note: I'm not a native English speaker.
[1] https://en.wiktionary.org/wiki/set_up#English
[2] https://en.wiktionary.org/wiki/setup
[3] https://en.wikipedia.org/wiki/Phrasal_verb