Cake Confusion

So I have a little tradition that I make these homemade cakes for my boyfriend on his birthday. He make me the cutest little homemade cards all year long with little cartoon character versions of me and "the kids" as we call them. Our "kids" consist of my twelve year old cat, Simba and our recently adopted Boston Terrier, Miha. I can't draw very well, but I'm an alright cook. Last year I made him a lemon chiffon cake with strawberries as well as a pineppale upside down cake. He doesn't like chocolate, so strawberries are pretty and tasty.

This year I decided to make a very Strawberry cake. I worked on it for about three and a half hours. I hand dipped strawberries in melted white chocolate and hand shaved little white chocolate shavings all over the top in my attempt to make it pretty. I handmade the frosting from fresh strawberries and everything. A couple of problems here. One the frosting sagged a little big. So it looks a little drippy in places. The other is it turned out a little dry. Although, that hasn't stopped me from sneaking into the kitchen and eating the cake straight off the cake plate, I need to know what the secret is to make a cake moist. As I'm nearing my thirties I've learned that women can be amazing support systems for each other. Whether it is, how do I get my laundry to smell better or how do I save my marriage, women have this beautiful way of helping each other out. So please ladies, help me and my dry cakes.