Festivals are fun places to be. Even more so if you can have sex in your tent. The feeling of being surrounded by thousands of other people while you and your partner go at it is quite a turn on. Think about it. The only thing seperating you from the outside world is a thin layer of canvas. Ooo-er.
For this reason it is advised to keep the noise down as even a groan or a moan can be heard outside. Of course that is up to you. If you are an exhibitionist then let rip with the sex noises, You can then emerge from your tent proud. But if you are not and want to get away with a little noise then try using music to mask your antics. Choose something like lil louis french kiss as this has orgasm noises within the song already. Hopefully the people outside will think it's a remix. althought the track is only four minutes long so you'll have to be quick!
When the lights go down
Most people have sex during the night. The night however, brings its own set of hazards. Be careful not to leave your torch or lamp on as this will project a horny shadow onto your tent wall and grant all those outside an interesting shadow play. If you want the lights on then get under the covers/sleeping bags and get all sweaty.
Get the T-shirt
Having been to many festivals I can vouch for the experience as some of the best sexual encounters I've ever had. I heartily recommend it if you get the opportunity. It feels like having nookie outside, but with the privacy, comfort and warmth you need to really enjoy yourselves.
Always practice safe sex. Especially if you meet some-one there and end up having coffees in your tent. You don't want to leave with any undesirable momentos...