Here are the simplest guidelines for what to do when you start a conquest match.
1. Each team has a planet and a research facility they can easily capture. make it your priority to get those asap.
2. After you have captured the research and planet next objective is the teleport gate.
3. Do not capture refineries. current state of the game makes it only worthwhile in the lategame to add some pressure on the enemy.
4. Farm kill those little npc ships whenever you have the chance to.
5. Hold the teleport gate. you can upgrade at it without having to go back to base, saving time.
6. Push one of the lanes. kill the enemy npc wave and using you wave as a tank try to destroy some of the enemy turrets. be ready to escape at any time.
7. Try not to die. the faster ships can not take hull damage well. if you are about to loose shields run! the larger ships can take some armor damage(grey part of the bar) before they need to retreat.
8. Teamwork is a key. stick together and wreak havoc.
9. Ultimately watch them surrender or if they persist, kill their base.