Europa is the fourth galilean moon and icy natural satellite of Jupiter. Terraforming Europa would be far easier than Io, but more difficult than Mercury, Venus, Mars, Ceres, Pluto and Luna. This satellite would first after the Moon need a new thick atmosphere. The atmospheric pressure would have to be around 7 bars. The atmosphere consists almost entirely of oxygen currently, and while oxygen is essential for breathing, oxygen levels that are too high can be fatal to humans. As such, nitrogen should be added as a buffer gas. The new atmosphere should be kept around 20-30% oxygen.
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.
Asteroids can be deployed to speed the rotation of the moon, 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, or a walk in the park if you don't mind the leaves.