Open Question: Sleepover nappy- Camping?

I'm going camping with my cousins, while our family go away for the weekend. I wet the bed, but my mum said having a nappy on hand would help? /:
I'm really starting to get worried, Pampers size 7, they fit me really well, but I'm worried they'll leak when I'm asleep?
And also, I find them really tricky to put on properly, my mum had a word to my oldest cousin (19), who will basically be in charge, and he said, If I needed help, he'd do it for me, but when they say 'help', I don't understand what they mean? What will he actually do? :S

Thank you so much in advance, I'm a nervous wreck at the moment :/

Source:
http://answers.yahoo.com/question/index?qid=20110717090055AACUnnB

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