Mindshift: "Mindshift" is designed to help young people cope through periods of anxiety using strategies based on Psychologist designed Cognitive Behavioural Therapy (CBT) techniques which help you relax, be mindful and develop more effective ways of thinking and coping with stress and anxiety.
https://www.anxietycanada.com/resources/mindshift-cbt/
Self-help guide produced by Anxiety UK to help you cope with anxiety:
Mood-juice self-help guide and workbook to help you cope with anxiety: