Yes, you CAN write a sex scene!
I know as writers we're supposed to be able to conquer the worlds we create and the characters we bring forth but there is a sticky little piece of fiction that makes some of us seasoned writers run for the proverbial hills.
In reality, writing sex scenes between characters, we all get flustered and confused even in our own lives but when we're alone it's almost like we're being asked to open up our darkest selves and pour it onto a page for others to read.
But it isn't, we have to remember that we're writing a character, a figment of imagination, our imagination and as such we're in control of it. We're not revealing anything of ourselves, only of the character we've created, that the character may enjoy a light bit of spanking before bedtime not us.
We need to be clear in our definitions of where we start and our characters begin, to map out their tendencies beforehand, that maybe the uptight star commander may like to be a submissive in bed, allowing the partner to take some physical control because their job (the gruelling fourteen hour shift) takes everything they have to give. And giving in to someone else and letting them choose when your tired out isn't always a bad thing.
To let your imagination flow into these spaces doesn't fill everyone with dread, but if it does you can always go for the old fashioned, 'their heated skin met, falling back into the arms of ecstasy they strove to find eros in each others embrace.'
Otherwise you let the reader fill in the blanks, but in doing so I think you allow someone else to decide the inner nature of your characters, the real grist and gristle of them. That you've handed over some of their depth to someone else to fill. When what most authors aim for is a real flesh and blood person you can see and feel and that includes their sex appeal to the opposite or same gender.
I'm not going to go into the whole gender bias now of heaving bosoms and thrusting rumps here, no not at all..... Just that you should have your own language of sexual desire, whether it gets it's fulfilment or not. Think of the many romances that have smouldered and burned yet have never been consummated, looks, smiles, even the way a person stands can be sexual, it's up to us the author to make it so.
Have a look at 'The Thomas Crown Affair' the scene with the chess game, which is sex played out in public on a chess board, it's all in the way the fingers move and the eyes meet. You have more to your imagination than just the pink and wobbly bits (which are fun to write about, trust me) but if you can't face it look for a more sophisticated way.
But for those of you who want to bite the proverbial cherry, then read on and learn a few things about body tensile strengths and the heights of tables versus groin heights.
Sex, we all know it, we've all had experience of it somehow or somewhere, from the films we watch to the pornography that tells us everyone should be hairless and have two balloons for breasts.
No, in reality there are tables that get in the way, pets that want attention at the wrong moments, guests that you forgot you gave a key to and people who are washing your windows at the wrong moment.
Forget the Karma Sutra, what most people get is a quick ten minutes of fumbling bliss, a quick swift change over because knees/backs/ankles are hurting and you can hear someone coming up the path!
Strive for realism, but remember the humour factor, condoms that don't fit first time, laughing at the position your in and the way everyone's bits wobble even then you don't want them to. Unless your character is a person who does this for a living (prostitute, concubine, gigolo) they are going to be nervous about starting out with someone new. Even if the blood is pumping and hormones are thrashing inside the bloodstream you still have nerves and a sense of humour.
Don't forget some people are silent as they make love, others are screamers, some growl, others purr, some like to fight and claw your skin, others just cling on so tight you think your going to pass out from oxygen starvation. Round out your characters, give them honest traits, like one guy likes red heads, but only with a good arse on her. Or a man who loves good shoulders on his men so he can feel small when he's being held close. What I'm saying is this......make them as real as you dare. Go as far as you dare to go and then go a little further.
The more you tackle the taboo the easier it gets to deal with, from what writers of erotic fiction call 'missionary vanilla' to the outer edges of 'knot play, suspension and silk work'. Let your inner erotic muscle work for you, and I don't mean for you to go on a orgy of pornography. The most erotic thing you have is inside your skull, without it we wouldn't be able to imagine what a person would feel like to our naked touch.
Clothes are important, the more dressed a person is the more erotic it can be, it depends on the writing and the way you utilise the language you have. I'll give you an example....
'Her skirt was always clingy, it spread out under her finger ends, smoothly and swiftly she straightened herself up, meeting his look with her own.'
'Her smooth silk skirt always clung to her thighs, taking it under her soft finger ends she allowed her hand to smooth the material down to her bare skin beneath. Seeing him watching her movements, seeing his eyes watch her hand stroke her own silk clad skin she slowly straightened herself up, meeting his hungered gaze with her own.'
The same experience, the same place but written differently, one from an emotionally bland place and one from an erotic or emotionally charged placement. Writing sex scenes isn't just about the bedroom, it's about the way your characters interact, do they find attraction to any of the other characters, and if so what do they do about it? We need to put these emotions into our writing if we want to seem as if we're writing realistic people and circumstances.
So if you find the sex in the bedroom a little difficult, just begin to include sexual thoughts, feelings, and emotions into your work and one day you'll find yourself writing a natural sex scene that comes from an interaction between your characters. If we freeze up our characters will too, relax and find it funny (which it can be trust me on this) you'll be able to write freely and openly.