While I don’t work in HR I have been in business for myself for years. Personally, I have never found cold calling effective, business is a relationship building exercise. I have invested heavily in networking and getting known in both my geographical area and wider. People need to know, like and trust before they buy; building relationships progress’s this faster.
Standing out as someone who has a deep knowledge, is an expert in your field is the aim.
Are there any networking groups near you that you could join?
I hope that helps,