Each person is different. So, it is not easy to say what time management skill will be most effective. From this perspective, you will have to find what works for you the best. Here are some suggestions that have helped me.
First, never put off what you can do now to another time. The more you get done when you have time, the better you will be in the future. There is something psychologically satisfying in getting something done and over.
Second, make a schedule and keep to it. If you know the various things that you need to do, then you can strategically plan. This strategic planning saves time in the long run.
Third, get ample rest. If you are going to be effective during the day, then you will need to rest. Along with this, maximize your mornings. If you can get a lot of work done by lunch, it will give you great encouragement.