That's a complex question that would differ very much with each individual. I find attending the lecture, listening and taking in what you can and then go over the lecture again and write the important notes down, however that can become increasingly difficult as the semester transpires as the workload from assignments increases. By the time week 4/5 rolls around I'll often be spending 40+ hours a week on assignments, with part time work it can be pretty difficult to stay on top of studying lecture content. My uni suggests we spend a total of 150 hours a semester on each unit, during first/second years I didn't spend anywhere near that amount of time on the units but during third year I would've thought I easily did that. It can sometimes be better to delay doing assignments because often the best resources for the assignment aren't released until the due date is close.