Put 1 torpedo on each ship so that you can launch multiple torpedoes and have them spread out. Aim torpedoes to where you think the enemy ship will be at the end of its turn not where it is currently. Later in the game, it does not matter as much because you will be flush with energy and your ships will be pretty strong regardless so it is fine to add modules to your ship in the strategic layer. This way, you can customize your ships to the specifics of the mission. In the early game, always wait until you are in the bridge screen before adding modules to your ships. So add a warp nexus before you move your ships and before you add modules. Warp nexuses give you free movement but also link the bonuses of your planets. Add warp nexuses to your planets before you do anything else. If no energy missions are available, go for a mission with a free tech since a free tech is really strong in the early game when you don't make a lot of science per turn. In the early game, energy is hard to get so any extra energy will really get help you beef up your ships.

when you first start a new game, on the first couple turns, try to go for missions that give you energy.

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