According to relationship expert Dr. Laura Berman, flirting is important to keep the spark alive in a long-term relationship. So, reignite the fire you have for your spouse with sweet and sensual flirting. Stare at your wife when she comes into the room. Let her catch you staring, and give her a wink and tell her she looks good. For girls, grab his biceps as he walks by and then nod approvingly. And yes, do not forget to hold hands while watching a movie in theatre or at home.