This Locked Alliance trainer mod for Civilization 3 Conquests only changes one thing: there is a locked alliance between two tribes. Normally you should play one of these tribes teamed with an AI player, or play with a friend for multi-player.
Play it one or two levels above where you normally play and use it to help you learn something about these higher levels. In and of itself it cannot make you a better player, but if you can play with somebody more experienced you're bound to learn some stuff co-operating.
Unzip the contents of the file to your Conquests scenarios directory. For most players this will be:
C:\Program Files\Infogrames Interactive\Civilization III\Conquests\Scenarios
To play choose the file with the two tribes that you want to have locked together. The names are in alphabetical order, for example:
There are 465 files in total (yes it did take a long time).