SpamAssassin Setup

Sorry if this is in the wrong forum.

I’m a little confused on how to get SpamAssassin set up properly. Apparently I have to log into SquirrelMail to get to the configuration. Once there I can choose from several predefined policies. However there are no descriptions of the predefined policies to guide me as to what they look for and there seems to be a few features missing.

With my previous host I set the weight for the various things SpamAssassin looked at. For example if the email was all HTML I could set it to 0.4. Where can I set this sort of thing?

I also can’t seem to locate the SpamAssassin training. Where do I go to train the program which messages are spam and which are ham?