When I saw the pictures of the cake Janice made a few months ago I told her she just had to share it with all of you!  

I made my son, Chris, a Buzz Lightyear cake for his 5th birthday. 
Anyone can do this cake, yes you can, really!!

I made three different sizes (4",6", 8") of round cakes, 2 of each size. I used Duncan Hines boxed cake mixes. I did one box of each in chocolate and in yellow. I added a little blue food coloring to the yellow cake mix to give it a green color to go with the theme. I split the mix into each size of pan. I layered chocolate and yellow (green) for each size to make it fun.
I use homemade butter cream frosting......
1 cup butter
1 cup veg. shortening
2 tsp. vanilla
4-8 tbs. milk
2 lbs. powdered sugar
Mix butter, shortening and vanilla until creamy smooth. Add alternately the milk (1 tbs at a time) and powdered sugar mixing each time until all sugar is used, but only adding enough milk to make frosting smooth enough to spread over cakes. Separate frosting into 3 bowls, half in one, then 1/3 in another bowl and 2/3 in the last bowl. Add coloring to each bowl to make your desired shade, I used yellow, blue, and green with yellow.
Be sure to let the cakes cool completely before you frost them. Frost each 2 layer cake first then stack them.
Stack cakes on top of each other off center (or centered, if you like), you may need to use 1 to 4 clean skewers to push through all layers to keep the cake from falling over. Pipe "dots" or "beads" around the bottoms of each cake.
I used my son's clean and new Toy Story Aliens, Buzz, and the rocket for the aliens. The sticks around the cake were party food sticks that I found at my (somewhat) local Super Wal-Mart. At the last minute (literally), my son said he wanted stars on his cake, so I used yellow card stock and a star shaped paper punch to make them......by doing this, the moisture from the frosting soaked through.  I would suggest using maybe some rolled fondant or just pipe the stars on instead.