You, Reader, are undoubtedly too young to ever have encountered a marriage manual of the type coming into popularity in the early 1900's. In them, the bride and groom (apparently no one ever had a sexual interaction on any other occasion!) were given instructions for having sex as detailed as those for building a birdhouse laid out in Popular Woodworking. These instructions came along with some major assumptions - that the wedding night would be the first time a woman would have sexual intercourse, that she would know little or nothing about sex herself, that the groom would know everything they both needed to know, and that all women would respond in the same way to the same stimulation.
The books' instructions laid out a course of action similar to the following: The considerate groom needed to spend ten minutes gently caressing her whatchamacallits before moving on to more purposeful stroking of her whoozits. Never mind that she didn't care to have her whatchmacallits touched softly, or at all, or that either of them even knew where they were located. The book told you to begin at Point A and follow directions before moving on to Points B, C and D. A sexual interaction was depicted as a type of Disneyland adventure where no one could get off the ride until they got off, so to speak. Or at least until he did.
Fortunately, such sex manuals have been outdated for more than 100 years, but their point of view still crops up all too frequently: "Want to be a great lover? Just buy my book, tape, programs, etc. and I will enlighten you about The One Right Way."
Sexual preferences (as opposed to orientation) are as varied as food likes and dislikes. One must take them into account every time two people come together, whether for the first time or the 500th. Tastes can change over time. New ones may be discovered. What might be considered an ideal experience for even most young women with an eager new lover would be unlikely to be so for most long coupled women and their maybe bored or preoccupied mate.
Take foreplay, considered by many men the pre-game warm-up before the main event. For many women petting, fondling and oral sex ARE the main event, the most reliable route to her orgasm. These good parts can now take their rightful place anywhere at all in any sexual encounter that the two want them featured.. Foreplay can be aft play, middle play or instead-of play That's the good news.
Have you seen the tee shirt slogan "Life is short. Eat dessert first"? The standard of sex used to be a meat and potatoes kind of routine with his finale as THE finale for both. The more problematic news is that if you're an eat dessert first kind of girl (or guy) or you have a strong preference for "small plates" kind of sex without the customary main course of penis-in-vagina intercourse, this has got to be communicated to your partner, perhaps even negotiated.
People being sexual for the first time will become accustomed to discussing their hopes, preferences and expectations for the upcoming event or communicating them nonverbally the way sex does often happen, but acknowledging that nothing about sex needs to be taken for granted.
Modern long-term couples will eventually get in the habit of checking what kind of sex is on the menu in exactly the same way they do for meal plans: "Let's just have Frosted Mini Wheats for dinner, okay?" or "I'm really not up for Big Deal sex. How about a hand job instead?"
Sex, then, can never become routine if it, like humans and their moods, is always open to the process of change.