Like Dennis mentions AF, you should prioritize and be willing to be flexible and improvise. If something grabs your attention during the show, and there will be thousands of examples of this each day, simply refer to your schedule to see what you will potentially miss by taking the new path, weigh the pros and cons, and make your decision. Experience does help however...
Knowing the size of each room and your chances of getting in or not, as well as how early you will have to be at a certain location to even have a shot. Personally, in recent years with all the madness and overcrowding, I have stuck to primarily smaller panels and not had too much problem. When the schedule comes out, I copy it into a document and edit, edit, edit. Usually I end up with at least two panels for every time of the day, then I mark the most important one and shoot for that one. It does help if you can have consecutive panels in one room. The most important thing to remember is just have fun and don't stress about missing anything. At any moment in time at SDCC there will be about one million interesting things going on. Just know that you are experiencing the one thing you were meant to be at that moment. Talk to everybody!
Also, I really enjoyed having my camelback at CV, so that will be with me again, and I will save enough on water to buy another LOTR maquette! And bring food, and snacks, and eat when you are waiting in line for a panel or otherwise. The food at this convention center is pretty awful. But we will all eat like kings after the show ends each night when "the freaks come out at night" in the Gaslamp.
So, just a few tidbits of advice from a seven year veteran.