Back in my second year of college (2008ish) I planned out a layout for a 2' by 4' space. I took the Marklin books, a piece of graph paper, and my tube TV and got to work designing a layout. I taped the Marklin book to the TV on a page that showed the different track and their part numbers. I then turned the TV to an all white channel so that the light would shine through. Moving the graph paper over this I meticulously drew out the track plan
This picture shows the paper that I taped to the TV
Here are my graph paper drawings. This is the outer main loops, which I later added a small siding at the bottom. (notice the curve turn outs on the left as well)
This is an inner loop that I planned to fill it in
After I finished this, I made a list of all the track pcs I would need. I then spent the next few months slowly collecting the pcs I needed on E-bay auctions. The reason I did this was because Marklin track brand new is very very expensive (I didnt want to spend $50 per curved turnout, or $5 for each pc of straight, etc.) There is still multiple hundreds of dollars worth of track that I managed to get at about 60% of full price.