First, well, you need to get some money... The easiest way is to take a machinegunner and shoot at the harvester, plant your c4 on it ( no mather tiberium you are free). Can also use grenadiers. Look at your momey growing up as you shoot the harvey... once you die, DO NOT buy a hum-vee or a buggy! Be ingi!! and repair your Harvey!it's 300 bucks, plus thoses comming from reparing...
Then go on a c4 run and damage whatever you can.... You'll die soon... Be ingi again, and look for biuldings to repair.... after that, funtime...

you can choose between saving your money for high class char, beacon rush or heavy armor... Once again, do NOT buy buggies or hum-vee... theses are only usefull when you need wo get to the other base fast... they are next to useless on the battlefeild....

Artillery/mlrs are good invesment at the beginning of the game.. they are cheap, and got a lot of punch, plus quite a long range... Don't waste any money for light tanks, buy flamers instead... or wait for stealth.... gdi, med will needed to prevent any early flame rush....

As soon as you can, mobius/mendosa are neede to defend the base, and tech should already be mining the corridors....raveshaw/sidney are good investment too, and should follow the main strike force, to help them... be sure to bring a sniper with you....

Everytime you die, start as ingie, and go back in the battlefeild to repair your freinds tanks....

tech will soon discover that they got A LOT of money... 3000 or so, if the harvester survived all the trips...

So it's time to buy tank for your whole team, or get a stealth tanks, stealth soldier and beacon... why the tree, try to figure out... It's my little secret.....

Gdi, buy mamoth and tech, and have mlrs support... 3 to 5 people should alwais stay base defence on no basedefence maps.... stealth soldiers are pesky, and an unexpected flametank is devastating...

Nod, keep tech in you base... mamoth are devastating....

Buy buggies and hum-vees when your team got the ennemy surrounded in their base... It's a fast way to get there... and support your teammates, or bring a beacon....

well, that's it!! hope it'll be usefull!