Need help in Scratch-building

I want to know what would guys recommend for a first time scratch-builder.
I have the project in my mind,but no experience.What kinda materials should i use?Where can i get some?How do i mold the parts?
Thanks for the help.
I have the project in my mind,but no experience.What kinda materials should i use?Where can i get some?How do i mold the parts?
Thanks for the help.