1. Tutor

If you have a passion for teaching and if you are an expert in any subjects or arts, you can become a tutor online. There are many students looking for an online tutor. Many websites like TutorVista or Tutor.com are available to help you. The only investment you need is a laptop and internet connection. You can select a time without interrupting your office hours.

2. Freelance writing

If you are a very creative and have the writing skill to put that into the paper you can try writing for newspapers, magazines, and websites.  They will pay you for each article according to the word content. Some multi-language websites also need translators. If you have the skill to translate a text into your regional language without losing its meaning you can also try the job of a translator. Payment will be per words.

3. Wash cars

If you don't have a car, you can spiff up those of your family, friends, and neighbors. You can earn extra money without many efforts. If you are staying in an apartment or flat the demand for this will be very high. There is no investment cost is associated with this.

4. Rent out your space

If you either have an extra room, extra house or space in your house you can also make extra money by renting out it to visitors and tourists.   Being a landlord is easy and profitable.  Airbnb, RelayRides, and many companies and tourist agencies now enable individuals to rent out things like spare bedrooms, vehicles not in use and extra space. Make use of this and earn extra income with less effort.

5. Babysitter

Babysitters provide care to children on their parents' behalf when they are away. In metro cities, there is the large demand for babysitters.  Use SitterCity, and ask family, friends, and neighbors if they could use a sitter or know of other families looking for one. It won't consume much of your time. If you like kids, this activity will provide you both return and pleasure.

6. Your own YouTube Channel

If you like making videos, this can be a source of income. If you know video editing only even too you can try the option of a youtube channel. You can earn money from Google Ads on your YouTube channel. If any of your videos went viral you can make more money.

7. Sell your hobby

You can earn an extra income by selling out your photography skill, paintings, singing etc. You can advertise your skills for weddings or other commercial events on your own portfolio site. You can approach many event management teams. They will provide you opportunities to showcase your skills and earn money.