Hi consider how you model positive behaviour eg. body language (eye contact, smiling, being serious) and verbal language such as praise, being consistent, fair, impartial and reminding children about rules and boundaries.
Page 204 of the EYE handbook
This type of positive reinforcement links with behaviourism and the work of behavioural theorists such as BF Skinner, Ivan Pavlov, John B. Watson and social learning theory Albert Bandura
page 286
If this is for the STL course you would also be looking at strategies involving reward schemes and sanctions eg. charts, pupil of the day/week/lesson, golden time,
TDA 3.4 pages 57+ supporting children's positive behaviour
Use your job contract, role, responsibilities and the setting's policy on behaviour to see what's expected of you.
Hope this helps a little