The basic strategy is this: Post interesting content consistently with relevant hashtags. Use a service like Hashtagify for hashtag ideas. Follow users in your niche and engage with their posts. I also know a couple of people who grew their Instagram accounts quickly solely depending on shoutouts from influencers. You can use a service like ShoutCart for that or contact influencers directly (most of them list their email addresses in their bios).
Some subjects are much better paid than others, so although you may love the idea of writing about travel (badly paid) a better bet would be a niche like finance (much higher rates of pay). Check out the Pro Blogger job board for high paid freelance writing jobs – other places to look might be Textbroker or you can look at the “gigs” section on Craigslist.
Robo-advisors are diversified investment accounts that are automatically managed by a computer algorithm (as opposed to a human money manager). If you want to invest, but don’t have the money, or don’t want to invest with a money manager, robo-advisors are for you! Robo-advisors make investing easier—and cheaper—so they’re perfect for new investors.