Welcome to the 405th! Just a heads up, you should use the search feature before asking questions because most questions have already been answered and people get kind of frustrated when they have to answer the same question repeatedly. I'm just trying to save you from getting chewed on for not searching.
Yes you can just start resining straight to the paper. you dont have to reinforce it with anything else. If you wanted to though i supposed you could reinforce it temporarily with cardboard until the resin hardens to help it hold its shape. I just did mine straight to the paper with no extra reinforcement and it turned out fine. Good luck
I'm using 110lb and tried using pure elmers glue brushed on, all it did was make a shiny coat and made the peices harder, but still soft enough to bend, waste of time, resining right away without reinforcing is alright, but I was playing around.