Hmm...What software do you use? It would not be real easy, I had a really hard time with it in my software. The base is a loft and Inventor has a hard time with organic shapes like this and really slowed everything down and made it much more difficult. I would start by drawing your scene in front of the base then extrude it into the base, after you remove the original design. I know that probably did not help to much but I wish you luck!