My guide to festival essentials

As I'm playing Glastonbury and Beverley festivals this month, I've been asking the age old question...

WHAT ARE YOUR FESTIVAL ESSENTIALS?

I've had many answers. From the sensible: "A tent, you idiot." 
To the absolute bizarre: "Imodium, so I don't have to go to the toilet."*

Here's my answer, in 18 seconds...

What are your essentials? Tell me in the comments below. PLEASE HELP! 

*Ingest Imodium for a weekend at your own peril.