I am an avid user of Linkedin and although it is frowned upon, i do often Link and invite people i do not know, especially potential candidates. I have been fortunate in that i have not been booted off for people stating they do not know me. But my question to everyone is what is proper etiquette after someone accepts your link?
I have at times sent a follow up mail and get mixed results.
I have held off calling candidates directly after linking, but i think it might be the best approach.

Was curious what others do? If you do call, how long after linking is proper?