So you've decided you should do an EPQ right? But what topic should you choose

? Here's some steps to help you narrow it down.
1. Make a mindmapThis may seem obvious, but people miss this step all the time then get stuck! Start with 3-4 broad areas you are interested in (eg. cricket, history, programming and fashion) on the first layer, then think about specifics you are interested in in those areas. Try linking ideas back together if that's appropriate. If you decide an idea isn't what you want to do then write down (briefly) why, don't just rub it out or delete it.
(also you can use this as evidence of planning when you put your EPQ together at the end)
2. Decide if you want to do a dissertation or an artifactIf you started out with no idea what you wanted to do, you may not have decided this before hand. Or you may like one of your ideas so much you've changed your mind about what you want to do. But it's good to have an idea which one you would prefer before settling down to any further ideas.
3. Pick your favourite 3-4 ideasChoose them from your mindmap. Then do a bit of source research...is it easy to find sources? Is it next to impossible? Do they all say the same thing/quote the same other source/are otherwise exceedingly similar? Are the sources relevant or are they just on the broad topic you've chosen?
These are all things to consider. If there's too many sources then perhaps consider narrowing your topic so that there's less to choose from, if there's not enough then try widening it a bit. If you can't find enough sources for your project then it's not going to be viable.
4. Consider other factorsIs your project going to be possible to complete in the time available? (more applicable for people producing a product, but worth considering nonetheless) Is it possible to reach a conclusion/judgement? Has it got enough depth to potentially write 5000 words on?
5. Pick your topicOnce you've considered all the questions above, you should be able to choose any of the remaining topics you have as they are viable (you may have had to go back and repeat steps if your original ideas were not viable). Pick your favourite and make a start analysing those sources you found! Remember, if you find (particularly early on) the topic isn't working for you, you can amend it to fit with the work you've done so far, or early enough on you can even restart as long as you evaluate why you did it! The joy of EPQ is it is all about evaluation and planning rather than the final project, so you can mess that up all you like as long as you evaluate it
Good luck with making your choices!