This will be one of the hardest things for you to do because you really want to start shooting, but a little patience will pay off later.
When you first open your camera and slide the battery into the battery slot, you will be pleased to find that there is probably juice in the battery and you can start shooting right away. What you should really be doing is getting out the battery charger and giving that power-cell a full charge. Not only will this give you more time to shoot once you start, it will start the battery off on the right foot. No matter what claims the manufacturers make about battery life and charging memory, you’ll likely get better life and performance from your batteries when you charge them fully and then use them right down to the point where they have nothing left to give. To check your battery level, insert it into the camera, turn on the camera, and look for the battery indicator at the top left of the LCD (Figure 1.1).
A second battery is a great accessory that you should consider purchasing. Nothing stinks more than being out in the field and having your camera die. Keeping a fully charged battery in your bag will always give you the confidence that you can keep on shooting without fail. Not only is this a great strategy to extend your shooting time, but it also helps to lengthen the life of your batteries by alternating between them. No matter what the manufacturers say, batteries do have a life and using them half as much will only lengthen their usefulness.
While you’re at it, consider buying a second battery charger, too. A quick search online pulls up third-party chargers that cost much less than the official Canon model.