Help with touching up my roots?

[~chels~]

So about a month and a half ago I dyed my brown hair blonde and it looks really cute. But now my roots are starting to show up and my hairstylist is out of town on vacation. I always go to her because she's a family friend and gives me a great discount. I need to get my roots touched up ASAP because it's starting to look horrendous!! lol I don't want to go to another hair salon so I've been considering using one of those root touch up things you can buy at the stores but I'm afraid I'll screw it up and end up paying more. Should I try it out or just wear a hat until my hair dresser gets back?? lol