I appreciate that you took the time to come here and ask this. It's hard for everyone involved when the meetings are lengthy.
Some things I appreciated as a parent:
Make sure the student's file is up to date.
When major evaluations or reports are done, have individual staff member meet with parent ahead of time to go over report with them, and to give them a written copy. This will save a lot of time.
Give advance copy of draft IEP to parents so they can review and make suggestions for changes to the accomodations or goals.
Know your school's routines, problem spots, administrator quirks, difficult people, etc and prepare parents as needed in a professional manner. For instance in our elementary schools teacher requests to the principals are frowned upon at IEP meetings and are sure to get the standard "We'll take that into consideration." answer from the principal. It's awkward for parents and leaves you thinking you haven't been heard. "We'll take that into consideration" at that school really translates into "it's best to go to the child's current teacher to chat with them about what they are thinking are the best teachers for your child, mention that to the case manager, who will in turn make the request to the principal". At the junior highs in the same district, the case manager brings it up in the meeting and asks the parents directly what they think would be a best fit. Go figure.
Have a box of kleenex at the table for parents who are hurting. Nothing is more upsetting than to have a child who isn't responding when you're doing all you can.
I greatly appreciated "out of the box" thinking. Giving a child a break with an aide 20 minutes before the end of the school day to vent from the stress of the day on the playground instead of exploding the moment they walk in the door at home or on the bus. An offer for a homebound teacher to meet in a non-traditional location (at the school conference room or library). Sometimes the best solution is one that hasn't been tried in the school yet.
Be flexible when it's in the best interest of the kid. Especially when the kids are on the fence diagnostically or who've responded well to early interventions and are in no-man's land diagnostically. Once our team knew what label would be best but the criteria were so stict that any kid who presented atypically couldn't get there. They worked to come up with examples to make it happen. Every single person at that table knew it was stretching it but quietly did what needed to be done. It didn't cost the district any more--it just lined up the right services and procedures.