https://help.behance.net/entries/23178543-ProSite-How-do-I-set-up-a-custom-domain-

On the Dreamhost Side:

From the panel,  Go to your  Manage Domains Page and make sure the domain is DNS only. If you have hosting on the domain, use the “remove” button under the “web hosting” column:

Once the domain is dns only, click the dns link under your domain name and add these records:

Custom DNS Options:

Name: subdomain, leave blank for naked/root domain

Type:  type of dns record, such as A record, Cname, TXT

Value: Target

Settings Needed for this setup:

Name:  Leave Blank

Type:  A 

Value: YOUR IP HERE

Settings Needed for this setup:

Name:  www

Type:  A

Value: YOUR IP HERE

Note: This guide has been created to help simplify setting your domain up. The service you are pointing your domain to, DNS can/might has changed. Always check the hosts official page to verify the records.