To optimise your study time follow these tips so you're not wasting valuable time.
1. Pick a study space
Choosing a space to study in which you feel comfortable and the least distracted means you dedicate that location to study and therefore do not end up studying in your bed which is never a good idea as you end up lying down and sleeping or napping. I know this from experience but it never helped.
2. Create a schedule
If you stick to a schedule from the beginning studying immediately becomes easier. It also allows you to evenly distribute time among the subjects.
3. Use apps to track progress
Theres apps for timetables, and apps where you can grow trees for keeping off your phone during study time.
4. Watch YouTube videos
There are many good videos out there especially for sciences such as Primrose Kitten and Freesciencelessons, also Mrbruff is especially helpful for quotes in English.