Maybe you could put your hands in your pocket, but keep your thumbs on the outside? This gesture indicates confidence. It could help hide your nervousness. Avoid crossing your arms across your chest. This gesture means that you don't agree with the other person, or you don't like them (unless it's cold, then it means the person feels cold).
Some common small talk topics include the weather, your current job/ school, your hobbies, and sports. Try searching "Small talk topics" on google for more examples. Try to avoid saying anything too negative, like "This weather is terrible! Rain ruins my plans.".
When making small talk, I've found it useful to ask open ended questions to the other person, based on what you are already talking about. For example, if the other person is discussing their recent camping trip, ask them "What other camping trips have you done?", once they have said enough about their current trip.
An open ended question allows the other person to give a detailed longer answer. This helps to prevents awkward silence.
Make sure you let the other person finish talking about the current topic, before shifting the conversation to another topic.
Another useful tip is to nod your head occasionally or say "mmm-hmm". This shows the other person that you are listening to them. This indicates that you enjoy talking to them.
Once you do small talk with a person a few times, you can do Medium talk! Medium talk fall into 3 categories: People you know and what they do, hobbies, and things that happen to you.
When talking to an acquaintance, stand 4-6 feet away from them, if possible. This is done to respect their personal space, since they don't know you very well. Increase the distance slightly when talking to a woman (by 1-2 feet). When you know someone well, you can stand about 4 - 1.5 feet away from them. Don't go closer than 1.5 feet, though. That would make them a bit uncomfortable.
To wrap up a conversation, turn slightly away from the person. Only by 15 degrees or so. You could also turn one foot outwards instead. These gestures indicate that you want to finish the conversation. If the other person uses these gestures, that's your sign to wrap up the conversation.
Hope this helps!