After refrigerating, we colored the fondant. We bought professional cake dye colors for the red and black since we wanted such rich colors. I don't know that regular food coloring would get a strong enough color if you wanted it to be really bright. Also, be prepared to have dyed hands because you knead in the color. Two days later I'm still trying to get all the red off my hands! Also, the longer the dye sits, the brighter it becomes. Our red wasn't as red as we've have liked it, but it became a truer red over time. Anytime you're dealing with the fondant with anything (whether it be your hands, or a rolling pin) at anytime during the whole process, make sure you spray it with Pam and keep doing this if it starts to stick again.
To make the cake, we started with an 11 x 15 sheet cake with 3 cake mixes. A frozen cake is easiest to carve because it doesn't break apart as easily. I cut it, stacked it, "glued" it with frosting, and carved the basic shape. Here is some of the carving taking place. A couple weeks ago, I made a 9 x 13 cake and did a smaller cake as a trial run to figure out how I'd carve it and if I was capable of it. I highly recommend a trial run!
This is the finished carved and crumb-frosted cake. We used chocolate graham crackers for the spoiler and chocolate donuts for the tires. We stuck toothpicks in a couple places to hold pieces together, but obviously just remember where you put them for when it's time to cut and eat the cake! There were a few spots that weren't as perfect as we would've liked them but we read somewhere that fondant is forgiving. As far as marshmallow fondant goes, this is not the case! If you see the three different pieces we used of graham crackers, we even had it draping in between the pieces and had to fill it with more fondant. The next step was to cover the cake with the fondant. We rolled the piece out on greased wax paper, and made sure the dimensions were as big as we needed them to be to cover the cake in one piece because it's virtually impossible to smooth two separate pieces together without being able to tell that's what you did. To cover the cake, it took us 8 different ways of starting before finding a successful way. It was a little nerve wracking because you only get one shot and the piece of fondant was so big it took 8 hands to get it on there! We had fondant rolled out on wax paper, then covered the top side with more greased wax paper. We slid it on a big cutting board, and started to wrap it under the cutting board, and peeled of the paper on top. We took that end, and started laying it on the cake, and slowly slid and unwrapped more fondant and layed it under the whole thing was covered. I hope that makes sense! Here it is right after we'd covered it. Please ignore my old lady-looking hands. In the picture, I'm trimming off the excess around the edges.
Decorating just consisted of dying white fondant a color and rolling it out and making whatever shape we wanted. To smooth out spots that needed it, we got our fingertips wet and just rubbed the spot until it almost melted the sugar and smoothed it.