Training for the Camino is an important part of your successful completion of your pilgrimage.  One thing to consider is walking with your pack.  At first you may want to carry it with little to no weight only water.  As time goes on begin to add weight a little at a time until you have your full weight or maybe even more.  Walking with a full pack is much different than walking with no pack at all.  As you train with your pack you will begin to build new muscles to allow you to carry the weight along the Camino.  Walking with a full pack regularly for a month or so before leaving is a big help with being used to the trail.  You might also find that your clothing choices need to be adjusted or even your foot ware.   You will also have the chance to test your ability to get your water bottle without removing your pack or even making the choice to use a water bladder instead.