Configure SPF record to send emails (Sender Policy Framework)

Doing mass mailings to prevent to go in spam folders the best way is to configure a SPF record ([login to view URL]) I decided to use [login to view URL] for web hosting and to send emails. by default bluehost is using this configuration: "v=spf1 a mx ptr include:[login to view URL] ?all" I see there are many spf web sites to configure: http://wiki.civicrm.org/confluence/display/CRMDOC/CiviMail+and+GMAIL+Yahoo+Hotmail+Spam-Bulk I need someone who tell me how to configure SPF records to obtain maximum quality mailings doing quick simple work I'll need to do it on many domains, on [login to view URL] is enogh to say in chat which lines put for SPF records