For Roman Catholics, a number of the differences with Eastern Orthodox which are easiest to notice are superficial. Roman Catholics have statuary while Orthodox Catholics have Byzantine style painted wood icons. Romans use Rosary beads and pray the Magnificat, while Orthodox have knotted prayer ropes and pray the Jesus Prayer. Romans use unleavened wafers and (in RCC Western Rites) distribute the blood of Christ separately and only to the Priests, whereas Orthodox use leavened bread and distribute both species (mixed together, on a spoon). Many other surface differences in practice also exist, but due to our shared history can be seen as parallels of each other.
Other differences exist which are more doctrinal in nature. These will be the main ones we focus on in this discussion. You may wish to start with the brief video on differences between Orthodox and Roman Catholics below.