When we go to Epcot (usually 4 days out of our 10 day stay) we enter the park at Rope Drop, and tour Future World until around lunch time. At that point, we wander into the World Showcase, and slowly work our way around. Most days, we stop in each country, or most of them. We might see a movie, or live entertainment. We might browse the shops, or grab a drink, or a snack. Maybe we sit down for a while, or stop at the African Outpost to play on the drums for a bit. It is a slow leisurely thing for us, enjoying the sights, sounds, flavors.
While it is possible to walk all the way around the World Showcase in a fairly short time (it is only a bit over a mile around the lagoon), we will generally take 6 or more hours just soaking it all in. We then end our evening watching Illuminations. It is nice also to walk slowly on the way out, and wait for one of the fountain shows. The water show is amazing after dark with the water lit up with colored lights.