The general tips that I follow when it comes to ramming-
1. Don't ram without armor. As an extension, don't ram when in critical armor- around 25% or lower. It hurts.
2. If the enemy's armor is down, it is an acceptable time to ram.
3. If you use Impact Bumpers, the effect will last for 5 seconds after activating. Using this, and then switching to moonshine will add the angular drag, which keeps your ship from turning away during and after the impact.
4. If I am taking fire from the target, I aim to ram one side of the ship in order to turn it in some other direction.