Here's a simple but extremely effective technique to generate creativity:

1. Work hard on a problem until you reach an impasse.

2. Take an extended break from the problem (it could be a week or up to a few months, it's your call).

3. Repeat

I was typing this up just as Joseph O'Rourke posted his similar answer. Hopefully this helps you.

Here's a simple but extremely effective technique to generate creativity:

1. Work hard on a problem until you reach an impasse.

2. Take an extended break from the problem (it could be a week or up to a few months, it's your call).

3. Repeat

For creativty, Take Breaks - Article

And a piece of historical evidence to consider:

When Isaac Newton was forced to return home from school due to the Black Plague, he began to generate vast swaths of groundbreaking ideas including laying the foundation for classical mechanics and calculus. His productivity lasted for decades.