Your love of hard work. Your dedication to the care of horses regardless of factors like weather, hours, machinery that goes kaput. Seriously. I helped on scholarship selection for one of the colleges in my state, and we scored on those lines, too. Let a positive attitude show through. You have goals and are going to have a great time on the path to achieving them. Right?
Use the best possible grammar and spelling you possibly can. I promise that will put you ahead of much of your competition. If you have to hand write the essay, make it legible with no stylistic curly cues and heart-dotted "i's." No text abbreviations. srsly
Good luck and have fun.