1) Start off homebase with one factory... makes production faster afterwards. Depending on your racial bonuses or how you want to play, develop the home planet to either research, economy or factories. Try to specialize a bit because your home planet is going to be the strongest planet you own until you find/conquer a better PQ planet in the early middle game (dependant on galaxy size and number of planets, etc)
2) I pump out colony ships and 2 scouts in the early game for the planet rush. Then after the initial 5K runs out, I build them as needed.
3) Technology is important in most stages of the game. In the early part, it's for trade so you can get more techs without too much researching. In the middle part, you need to get enough diplomacy for trading or conquering, depending on playing style. In the ending game, techs aren't as big as you're either winning by now, so keep it up, or the AI is kicking your tail all over the stars.
4) I build 1 factory as a rule to make production faster. Everything else is based on what I want the planet to do, i.e. research, economy, or production.
5) Grab anything you can that is 4 and up quickly. At PQ4, there are only 3 or 4 squares free and you won't be able to do much with it at all. However, leave your home system's "mini-planet" alone until you have your ships out colonizing the reachable star systems. Nobody will come in and snatch that planet away from you that quickly.
6) Listen to Citizen agnostangel. That ship customizer isn't there for a side game, no matter what Stardock claims. (No offense there Stardockers!

) Customize EVERYTHING, even if you don't want to make your ships look cool. Put the engines/weapons/defense/modules that you need as stock ships are not made to defend against the AI's adaptive attacks.
Starbases... build'em, love'em, and spam'em. These rather powerful little buggers (perhaps a bit too strong at
higher levels) make a big difference between a struggle for victory or an easy victory.
Diplomacy is a must. If you have no friends trading with you in the universe, you better have the strongest fleet, or you're playiing a losing game.
Last but not least, play how YOU like to play. There are a quite few victory conditions in the non-campaign mode, so make it a point to try for each one and see how each playing style suit you. Good luck.