There are a ton of great tips in this thread thank you all who commented. I will echo all those who came before in saying the larger the tarp the less the issues with rain (so far at least). I set mine up usually a 6 inches to a foot above my hammock ridgeline and that has served me well so far, but I have a very large tarp. I also usually have a 45 degree pitch to the walls during heavy showers. As they say, your mileage may vary..