How to start a blog and earn quickly?

I’ll skip the basics of setup and style and go straight to the simplest answer: generate traffic. The more traffic you get, the more options open up to you in terms of monetising - after a certain point, advertisers and brands will start approaching you, instead of you having to approach them.

The 8 major reasons that people don’t get traffic to new blogs are:

1. They write in high competition topics. Sure, everyone may be searching for information on Weight Loss, but if your blog post doesn’t appear till page 98 on Google, no one’s going to see it.
2. They write in low traffic topics. You can rank #1 for Purple Pigeon Poop in Google, but if no one is Googling it, it’s a pointless keyword victory.
3. They spend too much time on promotion. Why write a blog post and spend 10 hours promoting it on short term traffic sites, on accounts with only a couple of hundred followers? Instead, you can use that time to write ten more blog posts. Google assigns authority based on the amount of content. If two sites have great articles on a topic, the one with the most content (the bigger site) will often rank better.
4. They optimise off site instead of on site. They’ll share. They’ll pin. They’ll social bookmark. But they forget that the best way to generate traffic is to make the content easy to read and easy to share. Add subtitles for easy skimming, add a nice image with title, suitable for Pinterest pinning, add clear share buttons and a call to action to answer a question in the comments or share with their friends. Let visitors do the work of promoting for you!
5. They write on topics they think are interesting, but others don’t. What are people actually typing into Google? Probably not what you think. People Google questions - so a great place to get topic inspiration is Quora. Facebook groups and sites like Yahoo Answers are some other great ways to find out what your audience really wants to know.
6. They forget that traffic increases with time. Many people share their blog post, then feel as if its a failure because it only got a few views in the first week. That’s normal! Content can take up to 6–9 months to start seeing organic traffic and good content will increase in traffic as time goes on and it’s shared, linked to and increases in Google rankings.
7. They don’t write evergreen content. Don’t write posts that are only relevant today, this month or this year - you’ll be competing with far bigger news sites. Write content that will always be current - recipes, how to guides, humor, tips.
8. Their site doesn’t have a central topic. Sure, it may be fun to write about giraffes at the zoo one day, then your favourite recipe the next, but this confuses Google. You’ll only build up authority (and traffic) to your site if you regularly write about the same topics, so Google sees you as an authority on those topics.

The best you can do to get started is create a LOT of content on your site. See what works. Promote what does well, improve, ignore or delete what doesn’t.