The easiest way is to play the chilled campaign and put the speed to 50% or 25%. Pick the Ovoid ship as it is the smallest and always make sure to squeeze your ships together so you are just 1 ship. Sit back and use your shield whenever necessary and make sure to stay away from the very edge or the screen just in case enemies spawn. Don’t take the right path for any reason when given a choice. Be aware of your surroundings because a random projectile or enemy could crash into you if you aren’t careful. If you feel confident enough, you can use your shield to kill bosses because it wrecks them on Chilled difficulty. This is risky because if the boss shoots at you, you could lose a ship. At the end of any level, if it doesn’t say that you lost 0 ships; just start over. This shouldn't take too many tries as long as you are patient.