Set up the three email authentication systems

I am looking for a freelancer to set up the three email authentication systems for my domain. Here are the details:

Email Authentication Systems:
- DKIM (DomainKeys Identified Mail)

Ongoing Monitoring and Management:
- No, just the initial setup

DNS Settings:
- Yes, I have access to the necessary DNS settings for my domain

Ideal Skills and Experience:
- Experience in setting up DKIM and other email authentication systems
- Proficiency in managing DNS settings for domains