Shoot in mid-morning or mid-afternoon. "I recently went looking for rock wallabies, and I was reminded that if you want to get a good shot on fine-grained film, you shouldn't shoot too early or too late. Otherwise, you may not be able to set a high enough shutter speed to keep from blurring the picture. But if you wait until midday to shoot, the light is just too harsh."
Use a long lens. "A lot of animals are pretty spooky, so you can't get close to them. Reptiles are less skittish than mammals because they know they can get away. But a good zoom or a telephoto lets you fill the frame with the animal without scaring it off."
Use a tripod if possible. "Tripods are really valuable because any little camera movement can soften the image if you're shooting with a telephoto. At the very least brace the camera on a tree branch or a sandbag."
Let the animal tell you when to shoot. "Look at its eyes and ears to see how tense it gets, and don't wait too long or you'll miss the shot. It's better to get a loosely composed shot than none at all."
Take the shot no matter what. "When it comes down to it, with wildlife the main thing is to get the picture. Don't talk yourself out of it. With wildlife, action speaks louder than light."