I can think of several idioms for having sex, such as

1. a roll in the hay

2. get your leg over

3. get your rocks off

4. dance without pants

I would be grateful if you add more idioms to the above list

I've never heard #2 or #4, but #1 and #3 do not necessarily include sex.
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Thanks for your reply.

Actually, I heard the phrase dance without pants in a movie, I think it is not common because I couldn't find it in any dictionary.

But as for get your leg over, I came across it in Longman dictionary.

Here are the links to it.

1. http://idioms.thefreedictionary.com/get+leg+over

2. http://www.ldoceonline.com/dictionary/leg_1

and for get your rocks off, longman dictionary(http://www.ldoceonline.com/dictionary/rock_1 ) describes it as having sex with someone, what else can this phrase convey?

Thanks for your time
Whether or not you find it in the dictionary, if I haven't heard it (after 7 years and 45,000 posts), then it is not in widespread use.

'Getting one's rocks off' is just as commonly used for masturbation or in fact for any kind of extreme excitement or stimulation:

I bet uncle got his rocks off watching Bush Shock and Awe the Iraq people

We were just a friendly chatgroup and this guy apparently got his rocks off by driving us insane and making us as miserable as possible.

Or is this guy just some sort of sociopath that just got his rocks off by killing a bunch of animals?
Thanks for your explanation and nice examples.
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