What is the most important responsibility for construction Methods. How to maintained the construction project.?

Set-up a plan first concerning budget planning, official detailed drawing, procedure and specifications, manpower, safety preparation, adaptation of work on climate change, close coordination to focal point person and site workers defining work tasks.  Mostly in Oil & Gas project, all roles given to designated professionals and site workers must comply to project requirements along with HSE policy, Construction, QAQC procedure and work implementation at site.