[apache]

Well, I only recently got the game, so I am not hard and fast on my early game strategies. Obviously, colonizer production is a major part of it. One strategy is to just flat out make colonizers with my homeworld and then set up shipyards and start building scouts with my new colonies. Sometimes I like to start off by building a few base spaceyards first, then put the homeworld into full colonizer production, while the bases make scouts, transports, and more colonizers. But because those bases are so expensive and slow, sometimes I just set the homeworld to produce a couple scouts, then put it into rush production for colonizers.
Either way, I always have to use scouts. For the very early game, if there are just no decent planets in my home system, I will use a colonizer or two to find decent planets. But they do not do long range scouting, that belongs to my dedicated scouts. Usually, I use an escort or frigate hull with the basics, 4 engines, and everything else filled up with supplies and a single DUC if its a frigate (its amazing how useful a level 2 or 3 DUC is against a neutral race, even in the middle of the game). Though they are not as fast as they could be, the fewer engines gives them 33% more range before they run out of supplies. My colony ships are pretty standard, though. The basics, 5 engines, and a cargo container. Of course, once I develop light cruisers, I immediately make a new colony ship design for longer range and higher cargo capacity.
I know it probably would not work well on smaller maps, but I play with 254 system maps and don't even bother making a military for quite a long time. When I see an alien race, then I start up limited military production, but I usually don't bother with a military at all until I have a significant number of colonies and systems.
The one thing I always do is to make nearly all of my early colonies research colonies. But, this has its problems because without resource colonies early enough, I tend to start running out of resources pretty quick.