Olinda is about 6 km north of central Recife, and getting between the two is straightforward. The cheapest option is the bus: several routes run between Recife's centre and Olinda's historic district, with the journey taking 20 to 40 minutes depending on traffic. Taxis and app-based rides take roughly the same time in light traffic but significantly longer during rush hours — the coastal road that connects the two cities can back up badly.
From Recife's Guararapes International Airport, the easiest approach is a taxi or rideshare directly to Olinda; the journey takes 20 to 30 minutes. There is no direct airport bus to Olinda. Most visitors arriving by long-distance bus will come through Recife's main bus terminal (TIP) in the western suburbs; from there, take a taxi or rideshare directly to Olinda rather than changing buses in the city centre.
If you are based in Recife, Olinda works perfectly as a day trip. If you plan to be in Olinda for Carnival, stay in Olinda itself — getting back to Recife during the festival is slow and crowded.