Here's an overly simplified description of the process by which you can learn about, and participate in, more public meetings on more topics of public interest than you could possibly attend in person – without ever relying on someone else's account of what transpired at that meeting.
Identify the public body which has oversight or jurisdiction over the issue in question. There may be multiples of these, at the local, county, state and federal levels, plus occasionally a treaty organization or two that gets involved.
Identify the governing board of the body, and the individual members of the board. Your direct questions about agenda items will go to them.
Identify the staff member who is board secretary. They are your best contact for details like board minutes and notices of upcoming meetings.
Ask the board secretary that you be notified of upcoming board events, per the Open Meetings Act. Put any future dates on your calendar. Note that meeting times can change on short notice.
Ask for copies of board packets for upcoming board events, per the Freedom of Information Act, and probably because it's as easy as cc'ing you on an existing email list.
Determine if there are audio and video recordings of board meetings, and if they are streamed live online. Ask for details about access.
Identify a member of the public whose affairs are affected by the public body who needs assistive technology to participate in meetings, and work on their behalf to gain access to meeting materials in machine-readable formats.
Read minutes of past meetings. If those minutes are not online, request of the board secretary that copies be put online. Note that in most cases draft copies of meeting minutes should be available before they are approved at the next meeting.
Read agendas of upcoming meetings. In some cases, detailed agendas will be available, complete with supporting records which are intended to to help the board members make decisions. Ask the board secretary for information about any details which are not obvious from the published agenda. Note that agendas can change on short notice.
Contact individual board members in private regarding items on current and future agendas. If you are brief, concise, and narrowly focused, you can provide them with assistance in their work in upcoming meetings.
Contact the board as a whole in public to make a public statement about a topic. Note that although I leave this at the very end, this is what most people think about when they go to public meetings – standing up, all shaky, in front of a microphone and giving their opinion. By the time you have gotten to the mike, it's always best that your message (however popular or unpopular) is at the very least not a surprise.