There are a number of threads about early strategy where you can suggestions from people far more proficient than myself, but some basic things I've found (mostly hearing it from others on this board) helpful:
- If you're looking for practice, play with all the AI's set to pure good and play good yourself, just keep your military rating somewhat respectable.
- The larger maps seem to be more forgiving, since it usually takes longer to meet your neighbors and potential threats.
- If you're playing a large map or bigger and really want to run away with the game on a reasonable difficulty level, pick +2 speed so you can beat the snot out of the AI in the initial expansion phase.
- Once actually in the game, if your start looks bad (ie Earth is low PQ, no other good planets/stars around, or the minimap shows that you're in a small cluster several parsecs from any other star) keep hitting ctrl-n until you get something decent. It can be fun to play the bad starts, but if you're still getting the hang of things...
- For the initial expansion phase, put spending to 100% and set your ratios to 100-0-0 (100% military) and pump out nothing but colony ships and maybe a few scouts, colonizing the best planet around every star you find that has at least a 15+ PQ planet.
- Once you've got a decent number of planets, try switching to 70-0-30 to get started on the tech tree so you don't get too far behind.
- When your treasury is below 100 or so, move your spending slider back to a balanced budget.
- When the colony ship rush is over, switch to 40-30-30 spending and go for the following goals: produce enough military to keep your rating high enough to avoid threats, get your social infrastructure up to snuff (soil enhancement and habitat improvements are musts, and banking centers are no maintenence so you may as well), keep up in the tech race, try to beat the other civs to galactic wonders and trade goods, and try to secure and harvest as many galactic resources as possible (particularly the influence and military resources).
As I've said, I'm not all that good at the game (just now moving up to Bright AI), but the above should at least get you to a half-decent start.