I finally tried it! I bought the required camera back in October off of ebay, and just today I made the light blocker and started experimenting with 'through the viewfinder' photography. To learn more about what ttv is, here is an article.
These are some of the pictures that actually turned out, my mom took the pictures of the flowers!
These are the ones I experimented with. The flowers turned out much better! I think there is too much light getting in on the ones I took. I didn't fix anything on the pictures except for cropping, which could use some practice too. The first picture is of some wine bottles on my kitchen counter. The second one is the lifeguard chairs at the Spring Lake Beach, where I've spent many summers!