1. Build a Kol.
2. Build another metal mine.
3. Build infrastructure upgrade.
4. Send out scout.
5. Send out light frigate also as a scout.
6. When Kol is finished, select bomber squadron, twice shield ability and once the gauss cannon ability
7. Move the Kol to the next planet to exterminate pirates.
8. Give move orders to the colony frigate, as soon as only one pirate is left.
9. Rinse and repeat step 7. and 8.
10. Build two civilian research station (for the colonizing techs and the earthlike planets upgrades) and a military research station (Armor upgrades are godly, hp ugrades as well, one capital crew research for another Kol as soon as possible).
11. Build another Colony ship (your first one will soon have to wait long for antimatter to use it's colonize ability. A second one speeds this up quite fast.)
After this I use my two Kols to defeat pirates, colonize the planets, research some more military and civil upgrades.
I generally wait with building frigates (I just build some flak frigates very early to complement my Kols) until I meet the enemy. When I encounter an enemy colony (which is too well defended to just capture with one Kol) I colonize the planet next to it and build its defenses up (gauss guns, repair yards, hangars). Then I start building a fleet in earnest, wait until the AI looses one fleet in my defenses and then attack and overrun it. (Btw. this strategy will probably not work in multiplayer

)