As you are new to this. Thought more experienced may want a place to offer friendly advice.

First it is common to post rules for communities in the side bar. Normally just behaivior type things. Look at a few other communities on political parties and use what you feel in appropriate.

As the community grows. You may want to find folks you trust and ask them to help mod the group. This is mainly folks with the authority to delete posts that break said rules. Multiple people help limit the time offensive nsfw or outright advertising like posts (assuming they are rules you want. NSFW is required by feddit.uk as are a few others.) are up and causing issues.

Feddit UK really is a fairly good space people wise, but Any political forum attracts fecal exit points.

Others may have more ideas.