Anyone help with this CAD building?

[mintlemon (eyem)]

Newbie here! I’m trying to practice building organic shapes like shown in the images below. Not really sure how to start, can anyone guide me through this? Appreciate any help

[Lagom]

A good case for Rhino’s SubD surface tools. You’ll find tutorials on YouTube. Then you can do this kind of blobby stuff with hard details.

[encephalon]

if you want to try with nurbs, BlendSrf is one of your biggest friends, i am currently sitting on my laptop and have only v7 here which gave me a hick up in the continuity, so i exchanged the 2nd blend with sweep2, but i believe in v8 you can just blend both ways and the surface will be alright.

start with a sphere. cut it back behind the center, then blend it. mirror and repeat.

here i had to sweep2 but try with blending it both ways.