Where do I start?

Three tough truths:

1. You've got to do it

At the end of the day it's YOU that's got to do it, and it involves decision, and will-power - prioritise the topics you need to focus on, plan out your time and commit.

2. Revision takes time

There is no 'instant' version which will cut corners.   Sleeping with your book under the pillow doesn't do it.   Stop playing at other things, and start working at your revision. The less committed you are to it, the longer you've will have to spend on it. Put in place rewards at the end of your sessions and work towards realistically set goals

3. Revising is remembering, not reading

It's not 'revising' unless you're fixing it into your brain.   If you spend five hours working in your room, but you still can't remember it in the exam, you've spent 5 hours working, but you've not done any revision.  

Never just read your notes. You must always be DOING something with them to FIX the information in your brain.

There is no 'way to revise' which works for everybody.   All our brains work in different ways. The thing to do is to find the way that works for you.