There are always story ideas around, you just have to be open to them. One really good way of finding a story is by taking a look at the people around you. Is there anyone who piques your interest? What are they wearing, doing, saying? What do they look like? Any features that stand out to you? Take notice of their body language. Then think about why they are where they are today, for example if they’re on a train where are they traveling from/to and why? (Obviously that part is purely your opinion.) You now have a character and maybe you even have a storyline too. They could be running away from home, or even an undercover MI5 agent.
Also make sure to listen to the conversations around you. You might hear something interesting. The last time I listened in to a conversation, it was between two old ladies and they were discussing how many bananas they’d bought and the amazing value of them. Obviously I didn’t manage a story out of that one!
I’ve never been too good at the people watching side of things, but my favourite way is observing any kind of commotion/altercation. Just the other night, my neighbour was having an argument outside with his girlfriend. I sat on the floor next to the door, listening through the letterbox. Unfortunately, I didn’t manage to hear anything because my mum told me off for being ‘nosey.’ Yes, I guess I was being nosey, but it always feels better when there’s a reason for it. I was annoyed at her for the rest of the night for potentially preventing an amazing story idea.
Even if your mind feels blank now, just wait because your next idea may be just around the corner.