Great Invention

[Chasingcars]

Not really sure what section to put this in really ....but I have an idea for a kitchen invention which i believe could be as big as the 'spork'.
I dont think my idea exists so how do i go about seeing if it could be made and should i get a patent for it?
If I tell someone about it before it is patented how do i know someone else wont steal my design!?
Any advise appreciated!!