Of course you can make a DIY aproach.
But there are several levels of DIY.
1) Do you know how to phisically sculpt? Great! Now you need to digitalize that.
You can use something like this: http://www.123dapp.com/catch But you need a lot of cleaning to do of the model.
2) Or do you want to sculpt from scrach in a 3d Program. https://www.blender.org/
3) Or you can google for free 3D models https://www.google.com/search?q=3d+model+free
4) Now you need to make some slices. You need to import your object for example if it was made in sculpturis into blender and perform some bolean operations.
This requires some practice in blender, becouse you need to solve specific issues regarding the geometry of the model. Also, importing the geometry sometimes can be buggy.
5) Now you can prepare your slices on an ortogonal view so you see them at the same scale, and use them as a template to print them. Something primitive as a screen capture can work.
Some cleaning of the images may be required. http://www.gimp.org/