You need to start by doing something interesting. There are lots of things that qualify. Most are hard work. People will follow you if you spends days or weeks learning about something and then giving the 5-30 minute summary of the interesting things. Interesting is in the eye of the beholder, so you can pick which parts you want to call interesting - the important part is to make it interesting to your readers. (Truth is not a requirement, though I would urge you to stick to the truth)