When you arrive, check the times for the daily parades and if you don't care about them, FOR THE LOVE OF GOD, avoid Main Street and Fantasyland during that time!! If you are entering Disneyland during that time, you will not be able to get anywhere, the crowds take up the entire sidewalk and you will feel like a salmon trying to fight your way up against the current of people. Always wear comfy (not brand-new) tennis shoes for maximum walk-abilty. Snacks, food, and water are all allowed in the parks. Bring your own lunch and keep it in a locker to avoid such lines completely and save a few bucks. Try waiting 1-2 hours after the stereotypical 'lunch' and 'dinner' times to eat your meals in order to avoid a long line for food. Do the most popular rides as soon as the park opens when crowds are thinner you won't have to wait as long. Try to avoid major holidays or vacation times such as Spring Break. Weekdays are always better than weekends for getting on more rides, but the time of year is important, too. It can take 45-60 minutes just to get into the parking garage during that time, so come early if you'd rather spend that time in the park. Leave your hotel at least an hour before the park opens you will avoid the huge lazy crowd coming in to the parking garage 1-2 hours after opening. Stay at a hotel within ten minutes of the park.