Something to put your poncho in when you are inside, a big zip lock would work if nothing else. I sort mix it up between a poncho, a rain jacket and an umbrella just depending on how hard it is raining. I have a pouch for my rain jacket and I turn it inside out before I put it in there. I also have one for my umbrella. I have different lengths of rain jackets as well. If it's just supposed to be a drizzling rain all day, I'll take the shorter one. If it's going to rain hard all day, I have one that goes all the way to the ground and I wear it, it even has pockets in it, ain't no way anything but my shoes are getting wet when I wear that. It's not good if it's not going to rain all day because it's kind of hard to fold up small enough to put back up when it stops raining. I have one of the Disney Parks ponchos, they are a little better quality and cover me completely. The trouble with a poncho is your arms will be exposed and if you need to reach for anything, there is a possibility that rain is going down into the poncho and if there is any wind, it might ride up in the front getting your front wet.
If you have quick drying shorts/shirts take those.