1) By clearly defining role - responsibility amongst team members.



2) Implementing Configuration Management



3) Quality Control & Quality Management Process implementation

In order to implement any new process or inculcate/interoduce new process to be followed by team members is not always easy but we can adopt various methodologies to ensure team members are happy to adopt the newprocess.
i) Interoduce a new process after explaining the same in details.
ii) clearly mentioned the benifits and how it will help team mates project etc.
iii) keep track few days whether it's been followed until it's reaches in blood of team members.
iv) if it's not follwoed by major percentage of people than call for a meeting to discuss refinment of process or see where is the problem in following the same.
v) Get the feedback analyse it and if possible amend the process or try conveincing people as its not good to force until it's mandatory.