This is what I like to start out with (Advent)
1.Build Cap ship factory
2.Build 3 resouce extractors
3.Build two-three scouts (Most people prefer to build more than one scout so they can map out the system faster)
4.Build 5-10 skirmishers ( The more the better, but don't overdo it, those ships are weak, and the other races will soon be able to destroy them easily)
5.When Cap factory is done, build a Progenitor mother ship
6. build hostile tech stations (You usually need to get those illums fast, but it depends on your location of course)
7.Research illums
Now, you dont have to do no.7 that fast, but, like I said, most people who play as Advent usually want to get illums ASAP (As Soon As Possible)