Lock the study text away and forget where you hid it
You should be ok with a 17 / 18 revision kit – not a lot has changed and all changes are incorporated within the course notes
Watch the videos, read the notes and spend countless hours practicing questions from the revision kit
Don’t write your answer attempts in the kit itself – write your efforts on a separate piece of paper. That way you can attempt the questions multiple times without being influenced by previous efforts
And, whenever you hit a brick wall, post again on this site and I shall get back to you