Depending on the type of boat you have, myself i have a bowrider so its empty space (seats) in front. When you put a cover on a boat, which you should do because it keeps excess water out, even though boats are made for the water you don’t want it pooling or sitting in your boat for long period, leaves and other elements as well and the sun, the sun will kill your vinyl. When you put on a cover they make things called cover poles that go under the cover and pop it up a bit so that water can run down from the poles and off the cover, i have NEVER had any luck with this, water usually just pools around the cover, depending of coarse on whether the cover is a multi boat cover or made specifically for your boat. The cover i have now is a general cover. Here is a photo of my old boat with custom snap covers and a pole, see what i mean?
So i had this idea to use some left over wood from when i resided the front of my house, i thought the batten would be perfect, light pieces of wood that i could use to make a frame to lay the cover over and water could not pool. Since i have the tools and i learned a lot about measuring and cutting i was ready to go. I took the measurements and began cutting, the i used screws and my screw gun to attach the pieces. Then i had to test how heavy it would be to take on and off the boat. As i suspected it was nice and light and my measurements were perfect. In order to avoid the water pooling i needed to make sure the gaps between wood slats were spaced properly and with a properly tied down cover the water cannot pool!