Tips and Tricks for Beginners
You will lose. A lot. Do not worry about winning. Your first victories will be accidental through exploiting your enemy's mistakes and learning what to do in certain engagements.
Use the Guard, Force-Move, and Force-Fire options (CTRL and, ALT, CTRL+ALT respectively); You can make even more effective use of certain units this way. Also armored vehicles can run over enemy infantry with a satisfying splatter.
A massive part of learning to play RTS games is observation and experimentation. Watch those replays.
Keep an eye on your harvesters; as well as your enemy's. Attack theirs whenever possible. Harrassment and choking your enemy's resources is key. Know what building to attack and when.
Scout early; scout often.- but make sure to thwart the intel-gathering of your enemy, Get a radar up. Knowing what your enemy is about to throw at you is crucial to forming a counter; for that reason it is often more intuitive to throw up unit production; then refineries; unless going for the vehicles first, in which case a Refinery is required.
Building multiple production structures (mcvs and maybe temples/adv comms included) decreases buildtime.
Sometimes it is wise to selectively remove units from a composition of the enemy rather than let your units auto-target; Additionally, it can also be very wise to spread out the damage to the enemy units to cripple them.
Nod is the more advanced playstyle faction and trickier to play. Micro is required in many engagements to be efficient for BOTH factions- however unlike Starcraft and a bit more similar to Total Annihilation; C&C is more about the Macro than the Micro; If you see a unit fire; move, fire, move, they're likely being micro'd. Some units can fire on the move; others cannot. Almost every weapon in the game has some sort of delay- Imagine, then, that you are not an individual in an FPS- but commanding those individuals- You want them to dodge those tank shells, don't you? They can!
The Flame Tank is nod's Strongest tank- in terms of durability. It has the most health and armor. It is however quite slow.- but it's weaponry melts most light vehicles and infantry with ease; The mere sight of one of these things can often be enough to make your enemy quit- even if they have more units than you and could wipe you out.
If you've fought an opponent before; try to remember what they liked to do and if they won against you; Chances are they will try that strategy again!
Don't just spam a single type of unit; While this is a legitimate strategy; it is also often extremely unfun to be mobbed by hordes of bikes, mediums, or otherwise, very early on.
If you're feeling risque or think the other player is newer to the genre; pull back and give them more of a shot; If the enemy feels "limp" then they might give up and not want to play any more RTS games; and that is something we can't really afford for the genre; we need people to want to play RTS games.