If you do all pattern riding, it gets boring. If you have no routine at all, there’s really very little for your audience to look at. My favorite presentation in a parade is to do some pattern riding, some other “entertainment-oriented” stuff, and maybe also some freeform riding.
Beginners, even if they can’t freemount, should be encouraged to join the parade. It’s a great way to work on solidifying your riding skills. Bring a walker along if possible, to help with the likely frequent mounts.
The easiest pattern move is follow-the-leader. Make a line, and then the lead person can shape that line in many ways. Circles, snakes or whatever. Don’t attempt a figure-8 unless you’ve practiced it ahead of time. It probably won’t look good otherwise.
The other thing my small club used to do was to make “the V.” This looks the most impressive if your line goes from the tallest rider to the shortest. Everyone in the line takes turns splitting to the left or right, and joining hands. In the end, you have a line all the way across the road, with your tallest uni in the center. This is very visual and is one way to get a picture in the paper. You can turn this line into a V shape by having the tall rider go ahead of the others, so they trail off to either side like birds in flight.
If you practice, this line can even stop and do a stillstand. It’s pretty easy for riders of all levels to do stillstands when they’re holding onto each other.
If you have riders that can’t be in the pattern stuff, they should stay behind where the pattern is. This gives people a more clear presentation for them to see. Also if you have someone who just zooms around on a 45" wheel (my preferred modus operandi), they should stay to the front or rear most of the time, so the focus stays on the pattern stuff.
When you break up for other things, again try to keep it clear enough so people know where to look. When I’m on a tall uni, I like to ride up to the front of the people and make it look like I’m about to fall on them. Work the crowd! That’s the most fun part of all. There are many little comedy bits & things you can do. But I’ll stop now.