When you've added any custom asset fields, you can fill them with the information for individual assets by editing the asset.
Asset custom field values can be set by all team members in your project. Only Project managers can manage custom asset fields.
Editing custom field values
In your Firmhouse project, go to Assets in the sidebar.
Click the row of the Asset you want to edit.
Click Edit in the top right.
Update the values of the custom fields in the form.