Motivations, Social Structure, Communication
Motivation - Basically, this is what will make something deliberately do something. We sleep because we are tired, eat because we are hungry, exercise to stay healthy, etc.. These are all things we do because we have a natural motivation to do them; reptiles have only a few of the same motivations that we do, because they operate on a very basic level. Their basic motivation in life is to survive day to day. And they do this because they have the basic needs of food, shelter, and producing offspring that are their motivations of survival. Keeping this in mind as you train will help you better understand them.

Motivation based on need. A reptile doesn't need to come to you; a reptile doesn't need to spend time you; it doesn't need anything that has to do with you. A reptile does need food; a reptile does need solitude; a reptile does need a livable environment where it can thrive. So, how does this relate to training? This is about providing for it's needs; keeping it as happy and stress-free as possible before and after training. Training can be very stressful, so giving it a sanctuary where it feels secure is most important when it comes to training. You do not want an animal that is constantly stressed or on edge; this defeats your purpose. This is why husbandry is so important! Providing a home that gives it essential security can vaguely be a type of "final reward" for putting up with you. Once you release your animal into its home leave it alone, be done. Do not use it as part of your basic training methods.

Motivation based on want. One of their strongest motivations is food. This is typically used for training many furry and feathered animals. However, caution should be used when using this type of method for reptiles, as they can easily become overly excited or confused mistaking your finger or you for food during the reward process. The other problem is that a reptile only gets a few shots at performing before becoming full and disinterested in training so using smaller piece rewards are recommended. A different motivation deals with a comfort zone. In other words, I may provide something they want more than the situation they being placed in. This is how motivation uses counter conditioning. Example may be wrapping your reptile in a nice warm heating pad while you pet it on the head. They would much rather enjoy the warmth and tolerate your petting; making your time with them pleasurable and wanted.
Social structure - This is what governs an animals behaviors or interactions with other animals. This is part of the food chain that gives order to all living things. Reptiles are with no doubt at the top part of the food chain, so they should be treated with that respect. After all they did once rule the planet with savage dominance. Keep this thought in mind also, as you train. Reptiles are top predators because they excel in the use of strength, intimidation, and adaptability. If reptiles are forced to live together in the wild or as a same species captive colonies they will form hierarchies. This is most apparent in the wild with crocodilians and among komodo dragons, where space and food are a factor. Most reptiles prefer to live a solitary existence. They have several basic thoughts when encountering something in their environment which are: Is it going to eat or hurt me, do I need to eat or hurt it, do I tolerate it, or do I run away. This is a basic point of view of a reptile. In captivity you are already the dominate species, however your kingship will be constantly tried by your strength, will, and wits. So, as a king, rule with temperance, skill, and wisdom.
Communication - An expression of ideas, thoughts, or emotions through speech is often considered to be communication. There are other ways to communicate and they are used more often than speech. Writing, pictures, body language, and facial expression are some of the other methods used to express how one feels about their surroundings. Because reptiles can do none of these they are force to communicate through body language. It is very important to observe and understand what these gestures are, what they mean, and how they are used to express how they feel about their situation or environment. This is the area we will focus on more thoroughly, because this will tell you how or what you are doing in your training. NOTE: Watching a reptile's eyes during training will also give you an indication as to their mood or intentions; this is a skill that develops over time and varies by individual animal.
Learning Lizard Lingo
Hissing - warning, defensive display
False striking (closed mouth attack)- offensive display, warning to leave alone
Walking away - leave alone, 1st defensive response
Tail whip
- leave alone, offensive and defensive display
Tail curl - insecurity, feels threatened, defensive, readying tail whip
Wiggly tail - excited, becoming offensive
Puffing up - display of superiority, leave alone, I'm too big to eat
Shrug - leave alone
Open mouth (gaping) - general warning, warning to stay away, warning to bite, dehydrated
Posturing - up on all fours or show side view becoming defensive
Tongue flicks - curious, excited, exploring, tasting
Stiff body - feels insecure, doesn't want to cooperate, defensive
Closing eyes - contentment, giving up
Head bob - look I'm here, breeding signal, subtle warning
Head tilt/raise - curious, thinking
The wiggle - uncomfortable, may have to defecate
Defecation before handling - nervous, fearful, defensive
Circling - sizing up possible threat, defensive posture
Combinations - changes a defensive warning to offensive threats or attacks
Examples of body language and behaviors - Some are vary obvious while others are very subtle. Find as many as you can.

Anatomy of an iguana fight
part 1
part 2
part 3
part 4

Sidebody display
Follow eyes
Keep in mind many of these have dual meanings. As a keeper it your resposibility to know the difference. Individual personalities should also be taken into consideration.