Most importantly, Europa is within a huge radiation belt from Jupiter. The building of radiation deflectors around Europa would currently be highly impractical. A better approach is making an artificial magnetic field to deflect the radiation.
Europa would have to be heated so it can support liquid water on its surface. The problem is that if Europa reaches the shadow of Jupiter, it can freeze again. A few hundred tons of Sulfur Hexaflouride, the most powerful greenhouse gas known currently, could keep terraformed Europa warm. The new atmosphere of Europa would have to be composed of 70-79% nitrogen, 19-29% oxygen, and 1% of water, carbon dioxide, hydrogen, argon, methane, ammonia, and a layer of sulfur hexaflouride.
Asteroids can be deployed to speed the rotation of the planet, and to give it more heat. This can change the day from 1.78 Earth days to a 24 hour earth day.
After the ocean fully melts, Europa would most likely need artificial continents or floating cities due to the fact that the moon has vast amounts of water and a rocky surface would be deep within the ocean. A night on the beach.