Effective way of earning money

Freelancer.com is a good platform where the employer and the employees meet and work. However, you need to be careful and work with the employers who have positive feedback as the one's who don't have feedback or have negative feedback may scam you. Let me know if you find the site useful. All the best!

there is a lot, you can actually selected it because they are so huge, but you need to figured out which one can work for you to earn

What are those writing sites that you join? Try odesk, there are many jobs that you can apply.