There are two choices:
1. You can give them the 'Not Actively Looking' (NAL) link to your firm. You can find your firm's link on the Settings/Global page, or you can find an assignment-specific one in the assignment Info page in the 'Connect Link' section. The executive would then register with NAL and would be automatically connected to your firm (and to the assignment if you used the 'connect link'). If an executive does this, you will receive a notification with a link to their profile.
2. If you prefer not to use the NAL approach, you could have a registration page developed on your website. Ezekia has an ‘API’ that enables your web developers to build a registration page on your website. When this is filled in and submitted by the executive, a private profile (that only your firm can see) can be automatically created. This option will obviously take more development effort than option 1, but any good web developer will be able to do this for you relatively quickly. Let us know if you would like more information about this approach.