With this 5 day itinerary you will see all of Buenos Aires' highlights. I've taken care to plan each day geographically, diving into a new barrio each day, seeing as much as possible without jamming too much into a day.
What to know about this itinerary:
You can move these days around, play with the order of things. San Telmo is best on Sundays for the market. Recoleta's market takes place both on Saturday and Sunday. Downtown/Microcentro is livelier during the week and dead on the weekend.
If you don't have 5 days and need to cut a day, then cut Day 4.
If you have more time in the city, check out my other itinerary dedicated to off-the-beaten-path neighborhoods or add in one of these Buenos Aires day trips.