Like or As
like (preposition) + noun, pronoun or gerund
He swims like a fish. You look like a ghost.
I am like my brother. She looks nothing like her mother.
The windows are all barred It is like being in prison.
as (conjunction) + a finite verb
Do as I do.
Why don't you jog in the morning as we do?
But!
In colloquial English Like is often used here instead of As
Jog in the morning like we do.
Like + noun. As + noun
He works like a slave. (very hard indeed.)
He worked as a slave. (He was a slave.)
She used her umbrella as a weapon. (She struck him with it.)