The best thing you can do is help her to relax. Light some candles, have some nice and easy foreplay. Make her feel really special and comfortable with you, she will relax and it will be easier. I think its going to be a little tight anyway, but the relaxation will definately help. Go down there and lick around for awhile, get her juices flowing.

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Would you like more sex with that?

I wouldn't recommend sex, drugs or insanity for everyone, but they've always worked for me.