When you leave Faro airport (I assume you will have a hire car!) follow the signs in the direction of Faro.
After about 3kms you will come to an off ramp to your right marked Faro. Take it!
Follow the road into Faro (about 3 kms) till you come to a round about. Go 270º around the roundabout and follow the signs for parking.
You have arrived at the Forum Algarve shopping center.
In there, you will find an enormous Jumbo hypermarket.
To get back to Tavira, exit the Center and go back the the way you came, continue along the N125 following the signs for Lisboa until you come to the A22 motorway.
Take the off-ramp for Espana, Olhão and Vila Real and carry on for about 40kms. You will see the Tavira off-ramp.
