Experience categorically different things.

Creativity does not come from nothing. People sometimes have this hazy and rosy misconception that you can create marvelous things out of the void, but that does not happen in reality.

Creation is a result of successful and often unexpected link between items stored in the brain. Nothing comes from nothing.
Nothing ever could (yes, it is Julie Andrews in The Sound of Music). So it pays to store miscellaneous and on the surface irrelevant things in the cortical circuit of your brain.

As the number of items stored in your brain increases, the number of possible combinations increases in an explosive manner (just consider nC2=n(n-1)/2). So experiencing miscellaneous things is a rational approach to creativity.

Here, it is important to seek diversity in categories. Categorically same items, no matter how many are stored, would lead only to likewise properties when combined. If you store categorically different items, and successfully combine them, it would sometimes lead to real innovations0, although it is fair to say that the establishment of the combination itself is more often than not difficult.

The more difficult the establishment of the link, the more valuable when you succeed, although there is a fair chance that you end up as a hopeful monster.