subdomain format

[giants10]

If i wanted to have this format www.domainname.com/subdomain, changed to subdomain.domainname.com for wordpress blog. What steps must I take to change it to this format?

[gnomeontherun]

Whoever hosts your domain can help you with that. It could be your hosting account or your domain registrar, but basically there should be an option in those accounts to do this.

[demtron]

If you have never done this yourself, then your hosting company can help you with most of it. They may not actually DO it for you, but should at least be able to point you in the right direction. Also, you'll likely need to update your DNS zone to point the new subdomain to the right place.