Do a shitload of research! When i started on SteemIt a year ago i hardly slept for 2 weeks haha. Look through the FAQ and help of the official sites and search for steemit articles with good keywords like "tips" or "beginners" or "curation" and so on.

As a new user commenting will give you the very best success rate. Liking doesn't earn you anything and posting articles makes almost nothing without having at least 100s of followers, unless you post about software or something else you did for SteemIt or you post something absolutely amazing and get lucky.