Need strategy tips

First of all, what expansion/version are you playing?

In general, you'll need to focus a bit more on military early in the game if your opponent's homeworld is anywhere close to yours. It is simply not safe to invest in most civics until you can protect your economic investments. The exceptions to this is the techs needed to colonize volcanic/ice worlds, which are the only civic techs you should probably get early in the game.

Generally you'll want to get your first capital ship early because the first one is free. A colonizer or carrier capital ship is prefered in the most recent version of the game.

The best way to get more credits early in the game is to simply colonize more planets. Just make sure you upgrade the infustructure so that your income is no longer negative and they pay for themselves, especially after you factor in the profits from extractors too. Once you can no longer easily expand (probably meaning your opponent controls the rest), then you may have to invest in trade to expand your economy.

The first thing you should do at the start of the game is scout and figure out where your opponent is and what planets lie between you.

As a rule, if your opponent's homeworld is 4 or fewer jumps from your homeworld, you should always go with military labs, and if his homeworld is 8 or more jumps away, you should always go civic.  If he's 5-7 jumps away, it really depends on the planets that are between the two of you as well as your strategy.

Your first capital ship should either be a colony capital ship (Akkan, Progenitor, Jarrasul) or a carrier capital ship (Sova, Halcyon, Skirantra).  Colony capital ships are more economic, carrier capital ships are more military.

To increase your income, your best choice is to capture new planets.  Be sure to upgrade them with population infrastructure (they actually lose money until you've done this) and build all the extractors you can to harvest metal and crystal.  Later on, trade ports are a good option, but this requires at least half a dozen planets already under your control.

usually the AI players have a better fleet, but that only last a while, coz once i get a couple ice planets i can replace my losses and tear em apart.

you need to know every economic trick in the book to win.  

Not true; if you know every economic trick in the book, you can absolutely rip the AI limb from limb.  You only need the first chapter of tricks to beat them.

I dont know what all this "if its 4 jumps away concentrate on military" stuff is, but i find that military is the best to focus the majority of your efforts early on, I dont think the distance of the enemy homeworld makes a real difference because you need to boost you military strength early on anyway to at least give you access to lrm frigates and maybe a couple of weapon and defence upgrades to get a good fleet going

First of all, this is a general guideline, not a playbook.  Every situation is different.

When an opponent is sufficiently far away, you have enough time to get both your civic techs and then get your more advanced military units on the field before the actual fighting starts.  Of course you want your military ready to contest your opponent, but many maps give you enough breathing space to get some economy up first (particularly ice and volcanic colonization).  As well, every faction is always capable of falling back to carrier cap spam without getting any military labs, which is an alternative when civic labs are absolutely necessary but a rush is very likely.