The process is really quite simple. As you want to use a transport company as needed, you simple contact them by phone or email or WhatsApp the afternoon or evening before wanting them to pick up your pack. You will usually find information at the albergues regarding transport companies, but along the CF, I have used JacoTrans. One leaves the bag usually at the front desk or where instructed along with the transport fee usually in an envelope by a certain hour as instructed by the transporter. You will need to know your destination for delivery. Our packs have always arrived before us. The exception to pick up and drop off is for municipal albergues, although there might be a spot in towns where they drop packs off. The company will let you know if there is any problem with your pickup and delivery locations. The system works very well. Buen Camino!