Writing a CV is difficult, even when you've got something to write about! I'm not looking forward to overhauling mine, but as in future it'll be send to engineering firms and/or universities rather than everywhere I'd consider taking a summer job, it'll definitely need re-writing from scratch, rather than modification.
As you're young enough that I assume you will have plenty of space I suggest you consider putting in some of the following sections. They wouldn't necessarily be appropriate at a later date, or in certain styles of CV (there are several, and its worth looking into them!) but are perfectly acceptable before you've had a career!
-"Work and Volunteering Experience": Obviously only managable once you've got some. Once you've done your week or twos work experience you can add it on here.
- "Personal Profile": List your (positive) characteristics. 'I am a friendly cheerful person, who enjoys helping other people. I work well in a team, and individually -blahblahblah" List adjectives, atributes and adverbs you feel happy to describe yourself with (responsible, concientious, engaging, enthusiastic, diligent; then think up things that demonstrate them. This is the message you want to get across in your CV: And its also really useful for interviews. Solves the issue of the "Tell me about yourself" question.)
-"Hobbies and Interests": As previously mentioned, try to stick to ones that show what an employable person you are. Socialising with my mates does not count. Demonstrating your committment to orchestras does.
-"Specific skills": Useful if you're a self taught programmer or similar. Also a useful place to mention the fact you can use a computer, if you don't have any qualifications. "I am a competant user of MS Office including Access, Outlook and Publisher" is the sort of thing I usually have down, along with mentioning the engineering software I've learnt to use at Uni. Also a good place to mention competancy in any languages (I have a friend who regularly suprises people at interviews when she mentions being a native speaker of Russian: Shows they don't read her CV very well!)
-"References": These are important, remember its really rude to put someone down without explicitly asking them first! Two is usual: Try a teacher at school and then a family friend.
Good luck, the sooner you have the first one, the less painful writing all the others will be. It also gives you a start on future application forms (e.g. for college, uni etc).