What's good earning method to invest money to?

You need something that can provide you a passive income. With one hour per day you can't do much. This will be only enough to "manage". Some quick ideas:

- Sell Kindle ebooks (let someone else write them)
- Build an AdSense or Amazon Authority site
- Buy a site from Flippa that already has passive income
- Outsource the development of a small software that you then sell
- Pay someone to build a mobile app and earn from advertisments

Hope that helps!

Build a blog again.

You can outsource all the writing. One option is for example iwriter.com (very easy).

Simply order your articles and post them on your blog. Should not take more than 1 hour a day.

If you keep doing that you should have a nice blog within a few weeks.

Build a list from it, paid traffic is good only if you are collecting there info so you can market to them and make money

Start driving traffic to a squeeze page. A couple hours of setup and then you could dedicate your one hour a day to promotion. It's the easiest way to go.

Set yourself an attainable goal with the time you have and as Brent Stangel mentions set yourself up a nice looking squeeze page with something like leadpages.net or unbounce.com.

For a sure fire bang for your buck use media buys. Go to the sites that you can advertise on that have your niche traffic e.g. body building and market an affiliate product by buying an advertisement on their site. Rates are always negotiable and its pretty easy to do some research on what's hot in the muscle head market.

If I was to start again I would spend my week as follows:
Mon: 1 hour research on niche
Tue: 1 hour on niche sites I can advertise
Wed: 1 hour researching whats hot in the niche and compliments the site I am going to advertise on
Thur: Sign up to leadpages or unbounce.com
Fri: setup the squeeze page
Sat: Start negotiating the advertising spend (no less than 1 month of advertising)
Sun: Relax knowing that you have done everything you can

This is only high level but I know it works because that is the steps I have used for successful campaigns and affiliate marketing

Like many people mentioned build a list and market to them -It’s your personal ATM machine. Even if you’re a horrible marketer you can make lots of money once your list gets big enough.
When you focus your efforts on generating lots of leads you can be horrible at email marketing, horrible at copywriting and still make good money. Use your money to invest in the following traffic sources - Google, Youtube, Facebook PPC, Solo Ads, Forum traffic, Banner Ads. Those are traffic sources that will never let you down. Forget the rest, and focus on what
works and has always worked.

I don't know if you mean you have to invest $500 monthly or one time but I would suggest to build a system which takes you out of it as much as possible.

For example build a blog and hire writer to write product reviews for you then go to elance, odesk or here in the forum and hire somebody who is doing all the SEO work for you. Soon you blog will build up to a authority site.

Also have some optin forms on your blog or drive through your blog traffic to a squezze page to build a list of people who are interested in you content/products. That way you have already to streams of traffic your blog and your list!

PPC. Quick, fast, and allows you to test the niche out really quickly.