Using a swaddle wrap or sleeping bag can help them settle more easily and sleep longer when securely wrapped by giving them a sense of security during their early stages of development.
Ideally the babies room should be between 16°C and 20°C. You should check your babies sleeping temperature by feeling their chest, tummy or back to feel if they are too hot or cold - rather than their feet or hands which will often feel cooler that their core temperature.
Sleeping Bags come in a variety of weights (measured in togs - the smaller the number the lighter the weight).