I have a hard time coming up with original worlds and plots, but I need a portfolio of original work. Any thoughts on how to come up with ideas?
I will answer this question quoting Neil Gaiman. Here is his complete answer to the question "where do you get your ideas?". A particularly relevant excerpt:
You get ideas from daydreaming. You get ideas from being bored. You get ideas all the time. The only difference between writers and other people is we notice when we're doing it.
You get ideas when you ask yourself simple questions. The most important of the questions is just, What if...?
(What if you woke up with wings? What if your sister turned into a mouse? What if you all found out that your teacher was planning to eat one of you at the end of term - but you didn't know who?)
Another important question is, If only...
(If only real life was like it is in Hollywood musicals. If only I could shrink myself small as a button. If only a ghost would do my homework.)
And then there are the others: I wonder... ('I wonder what she does when she's alone...') and If This Goes On... ('If this goes on telephones are going to start talking to each other, and cut out the middleman...') and Wouldn't it be interesting if... ('Wouldn't it be interesting if the world used to be ruled by cats?')...
Those questions, and others like them, and the questions they, in their turn, pose ('Well, if cats used to rule the world, why don't they any more? And how do they feel about that?') are one of the places ideas come from.
That's all there is to it. You get ideas by daydreaming, and asking questions, and then going down the trail of questions until you find out where they lead.
The Ideas aren't the hard bit. They're a small component of the whole. Creating believable people who do more or less what you tell them to is much harder. And hardest by far is the process of simply sitting down and putting one word after another to construct whatever it is you're trying to build: making it interesting, making it new.
An idea is the beginning of a journey. As a writer, you have to follow this journey through, to the end. Every step of the way is both great joy and hard work.
Love Galastel's answer.
There's an anecdote out there about some writer or other asking an audience for five items that could not possibly be worked into a good story, with the challenge that he would write a story with those elements and sell it.
I don't recall the entire story, but 'smurfs' was one of the five elements--and the writer successfully sold the story he wrote.
The point was that almost any idea can become a sellable story.
Pick an adjective at random. Pick a noun at random. Make a story.
(DPT opens two new browsers and throws a dart at an adjective and a dart at a noun and gets:
repulsive violin. )
Ooooh. I'm seeing someone who has a violin which, when played, creates a cloud of emptiness. It repels people away. All people. This allows the violinist to move undetected through the streets of Vienna.