Question about Quantum Teleportation

[al onestone]

I'm trying to understand how a single photon is sifted out of a beam and given a unitary operation in so called "deterministic teleportation". In the teleportation scheme, we perform Bell State Measurement/Analysis on a pair of Alice's particles, of which one is already entangled to Bob's particle. This projects Bob's particle(photon) onto an unentangled pure state in the polarization basis (a qubit state). This particle then has a unitary operation performed on it to transform it to the original state of Alice's second particle. But in a real experimental situation, how does Bob figure out which exact particle to perform the operation on? and how does he separate it from the beam to perform the operation?