Does any one have any ideas how I can make a realistic shell for the new tortoise shell I'm making. I have no idea

You could make a paper mach'e shell. To get a shell shape blow up a balloon and only mach'e half.
Hope i helped!

This is a basic shell made from 1/2" high density foam.  I sewed the from fabric to give the appearance of the lines in a turtles underbelly.  The back shell is not quite a round shape with darts cut into the foam.  You can see the placement of the darts by the seams in the back shell fabric.  Let me know if you need more of an explanation. 

Julie

Thanks julie that's perfect I was wondering how to get the curves I was thinking of curving individual pieces with darts and then putting them together for shell. Mine is going to look very similar I see the head shape is almost the same great minds and all that. Its my first attempt at building anything so yeah. I did find with this shape head for the foam skull of the puppet to attach the mouth after the skull was built. Going against most rules but it was easier for me to get mouth shape right this way. 

I look forward to see your version.  This little guy is about 14" tall, so more like a fancy sock puppet.  The head is foam with a long neck sleeve.  The legs are only attached to the shell, so the turtle's head can move around quite a bit.

Julie

I was thinking of putting fleece skin over the foam head and then attatching it to inside of shell to allow a pulling into the shell.