My wife is a great flirt. With me, with her friends, with an audience. She knows that flirtation isn't just for people you're just getting to know. Flirtation is just as important years into a relationship as it is at the start.
Fatherly's refresher course on flirting with your partner doesn't have any big surprises; it's just a good reminder to get back in the habit. Just try a few compliments, some playful texts, or touching your partner as if you haven't seen them naked a thousand times in bed, in the kitchen and on the toilet.
The rules are basically the same as flirting with someone new, except that you already know your partner's preferences and boundaries. You don't have to resort to stunts like answering the door wrapped in cellophane. In a long-term relationship, it's an incredible turn-on just to treat your partner as if you were still discovering them.
Which, of course, you are. You can go far just by gazing at them like you did on your first date.
And of course you can reminisce about that first date, and any other memories of when you fell in love, which will excite some of the same feelings you had then.
Just don't flaunt your flirtation in public too much. No one likes a couple who make out at a party, or call each other good flirts in a blog post.