You can add traits to users and companies manually

On the page of a single user you can find the plus icon that allows you to override the value of a given trait or to add a new one altogether

On company pages you can do the same:

Additionally you can add traits to users from the People list:

Lastly, if you're a little more technically inclined we have a CSV trait upload tool on Replit. This allows you to upload a CSV with traits for users in bulk.
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