Gaieus, Aidus, Pilou thanks for your answers !
I think I'll try with SoapSkinBubbleTool.
Thanks again!

Hi Everyone! I'm new on this forum and I'll be glad if someone could help me. I would like to create 3d model of this object

So far I've done almost everything but now I'm facing a problem.
How can I create the thing that is missing on my object. This green shape on third picture

I hope someone could help me. Thank you!