Before you read the guide: this a very basic view on the game mechanics, if you're an advanced starcraft player you're probably already familiar with these things.
Gathering Resources
The first thing you need to know and respect is that when playing against another player,
you have to play fast! I always try to be a step ahead and not to get slowed by unecessary things. For example, you will not pick your nose at the beginning of the game watching your SCVs, drones or probes just standing around. As quickly begin to train more gathering units and send them all to collect minerals or gas.In StarCraft 1 it was very important to send each single worker to extract minerals by hand, Starcraft 2 has addressed this fairly efficiently, but it is good to break one worker away when it's being spawned and send him to one of the further ends of the mineral line so that your workers won't get bunched up together in the middle.
Another often neglected thing is a sufficient number of mining workers!For each of your bases (for most of the maps that's 8 mineral patches plus 2 gas geysers) you should have 30 workers. This number is not just random, but depends on the ideal saturation of each crystal and gas geyser, you want to have 3 workers on a single mineral patch and single geyser, that's most efficient way of gathering these resources,
it's a simple game mechanic.So with 8 mineral patches and 2 geysers times 3 workers on each we get the number 30.Of course it is not the end of the world if you've just on 25 workers, the important thing is to have sufficient number of workers before expanding further into the map.Always try to achieve high number of wrokers as soon as possible, but don't ignore the training of combat units. Whether you should focus on training gathering or combat units depends in most cases on how does your
pponent behave.So if for example you're playing as zerg and you see that your opponent is expanding and you choose not to rush him that gives you the opportunity to expand yourself, because you don't have to defend an early rush.
Advancing in technology
Again, the speed is what matters.You can't afford to spend half an hour thinking what is the right structure to built.This may be very hard for beginner to determine what is the right technology and combination of units to get. What you need is to simply play the game to recognize all the units and structures. This would be really huge article if I had to cover every single unit available in game and I wanted this to be just a quick overview.
Below is a tech tree for each individual race showing exactly the order of structures and technologies:
Also don't try at all cost to race quickly to top tier technologies such as Carrier, Ultralisk or terran Battlecruiser. I know many "recreational" players tend to fortify themselves in the main base untill the point they have fifteen Battlecruisers when they're ready to purge the map.
Believe me, in the game with opponent slightly above average they wouldn't even get to that point. Have a little confidence in your basic units (marines zerglings and zealots) and try to make the most out of them. You will see that game in which you meet with opponent from the beginning in minor battles is much more fun than playing a single 2 minute battle after 30 minutes of building massive army.
So When should I start training the army and how many units? This depends on lot of factors, but generally you want to start making at least some combat units as soon as possible to succesfully defend your base against potential rush or any initial aggression from the enemy.
As a protoss for example this could be a single stalker to prevent any reaper rush. But as I said all of this depends on your and your opponent's play style. Generally, you should always be able to face the opponent's army as efficiently as possible (you can not play the macro game if the opponent decides to rush you and keep the pressure on).
