I merely translated some of the stuff to Autodesk Maya, for you will have to work differently here, but the basic ideas stay the same of course.
It all starts with a basic sphere:
But, as a standard sphere has got way too many segments we will have to change the values a bit. Set it to 10 secments horizontally and 9 vertically.
Now make the middle horizontal segment of the sphere thinner by selecting the half over it and moving it slightly down and then the half of the sphere below it and, of course, moving it up:
Now, go to the top-view and select exactly one half of your sphere.
Extrude that half a few times (make sure "Keep faces together" is turned ON), until your sphere looks like this:
This will be your pig's body. Continue by selecting the 9 faces that are selected in the image below:


You will now have to add divisions to the faces. Use the values I used...
... and you will end up with something like this:
Once again select the faces shown in the images and now extrude them forward, one time a long way and then only a short distance (as always, do as shown on the pictures ;-) )
You will now have to select two faces in the front and scale them until it looks like this:
Extrude them one in order to scale the new faces down a bit and then extrude them again, this time inwards.
Adding ears and legs should be easy :) If you don't know how, check out the tut I got the inspiration from.
There is no need to make it very detailed for it's only a cartoon pig anyway, remember?
You create the eyes by selecting the faces you want them to be on, hit extrude, scale them down, extrude again (Hotkey "G"), this time inwards, extrude and scale the new face smaller once more and finally extrude one last time and move the new face outwards so it lines up with the original face:
Now smooth your pig.
You will notice that on your pig's behind there is still something missing: a tail.
You can easily create one from a polygonal helix.
make sure you have round caps turned on and also added some faces to those caps.
Finally scale it and move the tale in place.
Now add a pink shader and you're done.