to get started, assign some labour to agriculture so you have food, do some ships research try and stay positive for a small while, once you have a ship research or two, view rankings and rank near me, when someone say with 4-8,000 pr is in range who has 4+ planets attack him, then try and attack someone straight after.
build the ships in a separate tab (on firefox) or browser so you dont` have to wait to find him again on tha attack page.
once you`ve attacked and got at minimum 6 planets, grow the innermost 2-4
by grow i mean assing all labour to housing, make sure you have some on food to support the others, when you get a fairly high population, or the population is maxed, then plunder one or two of those planets.
this will give you some serious start up cash, and from there you do the reseat of your research .. infra reserhc probably 5 in agriculture rest in housing if you intend to support youself through plundering planets, if you want to support yourself with food then research more food and just do a few levels in housing first.
either or
anything further may be found in seperate players strategy guides on teh help centre > strategy forum
what i`ve put here is just a getting you started with some cash how you research the rest is really up to you.