Update on my progress:
I laid the 3/4" plywood on my garage floor and laid my track plan on top of it to trace. After getting most of it traced and cut, I set up what I had to lay the track again (this time in the train room) and get the final plywood cuts traced.
Once I had all of my plywood cut, I laid it on homasote and cut that to the same size (WOW is that stuff messy!!).
Now I have both the plywood and homasote laid out waiting for the risers to be put in. I feel like I've made quite a bit of progress in a week, considering last week, the room wasn't even painted yet!