301 redirect from vistaprint to wordpress

HI, I have recently learned that there is a 301 re-direct. I have a client whose has an old site on vistaprint, but a new site with me on wordpress. They have had the old site a long time so they have some traffic from there.

Is this when I should do a 301 redirect?

How can I do one from vistaprint to wordpress on another host?

Can you please tell me best practices for redirecting my clients old traffic to the new site and increasing the SEO for the new site.

Thank you!